DDOT Work Zone Temporary Traffic Control Manual 2006
DDOT Work Zone Temporary Traffic Control Manual 2006
DDOT Work Zone Temporary Traffic Control Manual 2006
Temporary
Traffic
Control
Manual
Guidelines and Standards
2006 Edition
d.
DISTRICT DEPARTMENT OF TRANSPORTATION
Traffic Services Administration
Government of the District of Columbia
Anthony A. Williams, Mayor
d.
D.C.
Edition
2006
Temporary Traffic Control Manual
Guidelines and Standards
indicates edge of
binder spine
Dotted line
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Figure 4-1. Five Parts of Temporary Traffic Control Zone ............................................. 4-5
Figure 5-1. Crosswalk Closure and Pedestrian Detour.................................................... 5-3
Figure 5-2. Sidewalk Closure and Bypass Sidewalk Operation ..................................... 5-4
Figure 5-3. Temporary Covered Walkway with Fencing at Intersection Corner ............ 5-7
Figure 5-4. Temporary Covered Walkway at Mid-Block................................................ 5-8
Figure 6-1. Use of Hand Signaling Devices by Flagger .................................................. 6-4
Figure 7-1. Height And Lateral Location Of Signs-Typical Installations ....................... 7-4
Figure 7-2. Commonly Used Regulatory Signs............................................................... 7-8
Figure 7-4. Warning Signs in Temporary Traffic Control Zones.................................. 7-16
Figure 7-4. Warning Signs in Temporary Traffic Control Zones.................................. 7-17
Figure 7-4. Warning Signs in Temporary Traffic Control Zones.................................. 7-18
Figure 7-5. Exit Open and Closed and Detour Signs..................................................... 7-21
Figure 7-6. Arrow Panel displays .................................................................................. 7-33
Figure 9-1. Typical Application: Closures on Curb Lanes .............................................. 9-5
Figure 9-2. Typical Application: Mobile or Short Duration............................................ 9-7
Figure 9-3. Typical Application: Mobile Operations on a High-Speed Road ................. 9-9
Figure 9-4. Typical Application: Moderate Duration or Stationary Operation ............. 9-11
Figure 9-5. Typical Application: Closure in the Center of a Local or Low-Volume
Road............................................................................................................ 9-13
Figure 9-6. Typical Application: Lane Closure on a Minor Street ................................ 9-15
Figure 9-7. Typical Application: Road Closure and Detour for One Travel Direction. 9-17
Figure 9-8. Typical Application: Road Closure and Detour for Two Travel
Directions ............................................................................................... 9-19
Figure 9-9. Typical Application: Right Lane Closure at Far Side of the Intersection... 9-21
Figure 9-10. Typical Application: Left Lane Closure at Far Side of the Intersection ... 9-23
Figure 9-11. Typical Application: Multiple Closures at Intersection ............................ 9-25
Figure 9-12. Typical Application: Closure in Center of Intersection ............................ 9-27
Figure 9-13. Typical Application: Closure at Side of Intersection (With No Parking
Lanes)........................................................................................................ 9-29
Figure 9-14. Typical Application: Closure at Side of Intersection
(With Parking Lanes) ............................................................................. 9-31
Figure 9-15. Typical Application: Interior Lane Closure on Multi-Lane Roadway or
Street.......................................................................................................... 9-33
Figure 9-16. Typical Application: Merging Taper Followed by Shifting Taper on
Multilane Road.......................................................................................... 9-35
Figure 9-17. Typical Application: Multi-leg Intersection.............................................. 9-37
Figure 9-18. Typical Application: Sidewalk Closure and Bypass Sidewalk Operation 9-39
Figure 9-19. Typical Application: Crosswalk Closures and Pedestrian Detours........... 9-41
Figure 9-20. Typical Application: Covered Pedestrian Walkways–Mid-Block
Locations .................................................................................................. 9-42
Figure 9-21. Typical Application: Covered Pedestrian Walkways–Corner Locations at
Four -Way Intersections ........................................................................... 9-43
Figure 9-22. Typical Application: Construction Dumpster Located in Parking Lane... 9-44
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APPENDICES
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
LIST OF ACRONYMS
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District of Columbia
Temporary
Traffic
Control
Manual
Guidelines and Standards
2006 Edition
d.
DISTRICT DEPARTMENT OF TRANSPORTATION
Traffic Services Administration
District Department of Transportation
Government of the District of Columbia
Frank D. Reeves Municipal Center
2000 14th Street NW
6th Floor
Washington, DC 20009
Web addresses:
DDOT: http://ddot.dc.gov
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
This Manual is the District of Columbia’s version of Part 6 of the Manual on Uniform
Traffic Control Devices (MUTCD) 2003 edition and either meets or exceeds the
requirements for the temporary traffic control established by the Federal Highway
Administration. This manual may also be accessed on the DC Department of
Transportation web site at http://www.DDOT.dc.gov. Future revisions to this manual will
be posted on the web site only and it will be the responsibility of the holder of this
manual to periodically check the web site and replace revised sections.
Temporary traffic control installations shall be reviewed daily to ensure the functionality
of the temporary traffic control devices and compliance to this Manual. These reviews
shall be documented on a weekly basis including detailed information as warranted for
the type of operation, using the Daily Checklist for Temporary Traffic Control form and
the Field Inspection Report form supplied in the next two pages.
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
• Arrow displays and Portable Changeable Message Signs properly aligned and
maintained.
(Name)
Location: _____________________________________
Date: ______________
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Inspected By:
Worksite Location:
Comments:
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
SECTION 1 - INTRODUCTION
Standard:
Traffic control devices shall be defined as all signs, signals, markings, and other
devices used to regulate, warn, or guide traffic, placed on, over, or adjacent to a
street, highway, pedestrian facility, or bikeway by authority of a public agency
having jurisdiction.
Any traffic control device design or application provision contained in this Manual
shall be considered to be in the public domain. Traffic control devices contained in
this Manual shall not be protected by a patent or copyright, except for the Interstate
Shield and any other items owned by the FHWA.
Guidance:
The need for standard controls is especially acute during roadway temporary traffic
control operations. Abnormal conditions are the rule, and therefore, traffic is
particularly dependent on design, placement, and uniformity of traffic control devices to
direct and guide it safely and efficiently through what would otherwise be hazardous
areas. The constantly shifting and changing nature of work zone activity on or adjacent
to the roadway may require frequent readjustments of traffic control devices in order to
handle new situations. Thus, the proper and adequate placement of standard highway
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signs, signals, pavement markings, channelizing devices, and traffic control devices on
roadways in work zones is a continuous responsibility of officials having authority and
jurisdiction over the particular roadway. This responsibility includes periodic daytime
and nighttime inspection of existing devices and conditions throughout the duration of the
temporary traffic control operation.
This Manual is issued to promote a uniform standard of traffic control associated with
SPECIAL EVENTS, INCIDENT MANAGEMENT, and WORK AREA PROTECTION
along the streets and highways of the District of Columbia. The standards, policies, and
objectives contained in this Manual are intended to furnish information and guidance to
personnel authorized to do work on the highway right of way and are not intended to
establish a legal requirement for installation. Good engineering judgment must be used
to arrive at the best traffic controls for a particular worksite, depending on the nature of
the activity, location and duration of work, type of roadway, traffic volume and speed,
and potential hazard. Thus, while this Manual provides guidelines for design and
application of traffic control devices, the Manual is not a substitute for engineering
judgment.
It should be recognized that it is not feasible to cover every conceivable situation. The
objective of this Manual is to illustrate many of the typical worksites and to describe
many common conditions encountered. When circumstances occur which are not
specifically covered in this Manual, or which require modification of the instructions
contained herein, the judgment of the various levels of operating supervisors must be
relied upon to meet the basic objectives. When warranted, the appropriate District
Department of Transportation Engineer should be consulted to select or tailor the proper
traffic control devices.
Support:
23 CFR, Part 655.603 adopts the MUTCD as the national standard for any street,
highway, or bicycle trail open to public travel in accordance with 23 U.S.C. 109(d) and
402(a). The “Uniform Vehicle Code (UVC)” is one of the documents referenced in the
MUTCD. The UVC contains a model set of motor vehicle codes and traffic laws for use
throughout the United States. The States are encouraged to adopt Section 15-117 of the
UVC, which states that “No person shall install or maintain in any area of private
property used by the public any sign, signal, marking, or other device intended to
regulate, warn, or guide traffic unless it conforms to the State manual and specifications
adopted under Section 15-104.” Section 15-104 of the UVC adopts the MUTCD as the
standard for conformance.
The Standard, Guidance, Option, and Support material described in this edition of the
D.C. Temporary Traffic Control Manual provides the transportation professional with the
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information needed to make appropriate decisions regarding the use of traffic control
devices on streets and highways. The material in this edition is organized to better
differentiate between Standards that must be satisfied for the particular circumstances of
a situation; Guidance that should be followed for the particular circumstances of a
situation; Options that may be applicable for the particular circumstances of a situation;
and Support that is informational.
Throughout this Manual the headings Standard, Guidance, Option, and Support are used
to classify the nature of the text that follows. Figures, tables, and illustrations supplement
the text and might constitute a Standard, Guidance, Option, or Support. The user needs to
refer to the appropriate text to classify the nature of the figure, table, or illustration.
Standard:
When used in this Manual, the text headings shall be defined as follows:
• Support - an informational statement that does not convey any degree of mandate,
recommendation, authorization, prohibition, or enforceable condition. Support
statements are labeled, and the text appears in regular font. The verbs shall,
should, and may are not used in Support statements.
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Support:
When the normal function of the roadway is suspended, temporary traffic control
planning provides for continuity of the movement of motor vehicle, bicycle, and
pedestrian traffic; transit operations; and access to property and utilities.
The primary function of temporary traffic control is to provide for the safe and efficient
movement of vehicles, bicyclists, and pedestrians through or around temporary traffic
control zones while reasonably protecting workers and equipment.
Of equal importance to the public traveling through the temporary traffic control zone is
the safety of workers performing the many varied tasks within the work space.
Temporary traffic control zones present constantly changing conditions that are
unexpected by the road user. These create an even higher degree of vulnerability for the
workers on or near the roadway (see Section 5 on Pedestrian and Worker Safety). At the
same time, the temporary traffic control zone provides for the efficient completion of
whatever activity interrupted the normal use of the roadway.
Consideration for road user safety, worker safety, and the efficiency of road user flow is
an integral element of every temporary traffic control zone, from planning through
completion. A concurrent objective of the temporary traffic control is the efficient
construction and maintenance of the highway.
No one set of temporary traffic control devices can satisfy all conditions for a given
project. At the same time, defining details that would be adequate to cover all
applications is not practical. Instead, Part 6 of the MUTCD displays typical applications
that depict common applications of temporary traffic control devices. The temporary
traffic control selected for each situation depends on type of highway, road user
conditions, duration of operation, physical constraints, and the nearness of the work space
to road users.
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Standard:
Temporary traffic control plans and devices shall be the responsibility of the
authority of a public body or official having jurisdiction for guiding road users.
There shall be adequate statutory authority for the implementation and
enforcement of needed road user regulations, parking controls, speed zoning, and
incident management. Such statutes shall provide sufficient flexibility in the
application of temporary traffic control to meet the needs of changing conditions in
the temporary traffic control zone.
Guidance:
The temporary traffic control plan should start in the planning phase and continue
through the design, construction, and restoration phases. The temporary traffic control
plans and devices should follow the principles set forth in this Manual and Part 6 of the
MUTCD
Option:
Temporary traffic control plans may deviate from the typical applications described in
Typical Applications to allow for conditions and requirements of a particular site or
jurisdiction, subject to approval by the Work Zone Safety Branch.
2.2 RESPONSIBILITY
Standard:
• Supplying flaggers and other personnel trained in work zone traffic control.
• Calling “Miss Utility” before digging, and notifying the District Department
of Transportation 48 hours in advance of starting work.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
• Monitoring traffic control devices for temporary traffic control zones and
removing them as soon as they are no longer needed.
2.3 TRAINING
Standard:
Each person whose actions affect maintenance, construction, utility, and incident
management – from the upper level management personnel through field personnel
– shall receive training in traffic control appropriate to on-the-job decisions each
individual is required to make. Only those individuals who are qualified by means
of adequate training in safe traffic control practices and have a basic understanding
of the principles established by applicable standards and regulations, including
those of this Manual and the MUTCD, shall supervise the selection, placement, and
maintenance of traffic control devices in work and incident management areas.
The contractor or agency shall designate a competent traffic safety officer who shall
be thoroughly experienced in and qualified for maintenance of traffic safety control
work. Prior to commencing work requiring traffic control management, the
contractor or agency shall submit, along with the “Application for Public Space
Permit,” the name of the traffic safety officer and any designated substitute. The
District Department of Transportation shall have the right to require proof of
experience and qualification of designated traffic safety officers. Certification by the
American Traffic Safety Services Association (ATSSA) shall be the minimum
evidence of training. The traffic safety officer shall be present to supervise the
placement and removal of traffic control devices for all phases of work.
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Standard:
The following select words and phrases have been incorporated from Section 1A.13
of the MUTCD along with some additions for convenience in using this Manual.
Additional words, phrases and references exist in Section 1A.13 of the MUTCD and
shall be applicable when such definitions are not within this Manual. When used in
this Manual, the following words and phrases shall have the following meanings:
Advance Notice (24 Hours) (48 Hours): One or two normal working days in
advance as specified. Saturdays, Sundays, and holidays excepted.
Arterial: Any U.S. or Interstate numbered route, controlled access highway, or other
major radial or circumferential highway designated by the Council of the District of
Columbia as a part of the arterial system of streets or highways.
Bicycle: A manually powered vehicle consisting of a seat, two wheels, two pedals,
and a handle bar.
Building Line: The line established by law, beyond which a building should not
extend, except as specified by law.
Central Business District, (CBD): That area within the following boundaries
(including sidewalks): Beginning at 23rd Street and Massachusetts Avenue,
Northwest, then east along Massachusetts Avenue to Second Street, Northeast, then
south on Second Street to D Street, Southeast, then west on D Street in a line crossing
Virginia Avenue, Southwest, to 14th Street, Southwest, to Constitution Avenue,
Northwest, then west on Constitution Avenue to 23rd Street, Northwest, then north on
23rd Street, Northwest, to Massachusetts Avenue, Northwest.
Centerline Markings: The yellow pavement marking line(s) that delineates the
separation of traffic lanes that have opposite directions of travel on a roadway. These
markings need not be at the geometrical center of the pavement.
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Changeable Message Signs: Signs that are capable of displaying more than one
message, changeable manually, by remote control, or by automatic control. These
signs are referred to as Dynamic Message Signs in the National Intelligent
Transportation Systems (ITS) Architecture.
Channelizing Line Marking: A wide or double solid white line used to form islands
where traffic in the same direction of travel is permitted on both sides of the island.
Civilian Crossing Guard: Any person, other than a police officer, authorized to
direct or regulate traffic.
Clear Zone: The total roadside border area, starting at the edge of the traveled way,
which is wide enough to allow an errant motorist to stop or regain control of a
vehicle. This area might consist of a shoulder, a recoverable slope, and/or a non-
recoverable, traversable slope with a clear run-out area at its toe.
Collector Streets: All streets designated as collector streets on the current District of
Columbia Functional Classification of Street Map, the latest copy of which is on file
with the Office of Policy and Planning.
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D.C. Vehicles and Traffic Code: DCMR Title 18 of the District of Columbia
Municipal Regulations, “Vehicles and Traffic,” as amended.
Delineators: Retro reflective devices mounted on the roadway surface or at the side
of the roadway in a series to indicate the alignment of the roadway, especially at night
or in adverse weather.
District Forces: All employees and/or work crews of the District of Columbia doing
work in the right-of-way.
Downtown: The original commercial area between the Capitol and the White House
bounded generally by North Capitol Street on the east, Pennsylvania Avenue, N.W.
on the south, 23rd Street, N.W. on the west, and Massachusetts Avenue, N.W., on the
north.
Edge Line Markings: White or yellow pavement marking lines that delineate the
right or left edge(s) of a traveled way.
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Guide Sign: A sign that shows route designations, destinations, directions, distances,
services, points of interest, or other geographical, recreational, or cultural
information.
Highway: The entire width between the boundary lines of every publicly maintained
way –in other words, the entire area within the right-of-way, where any part thereof is
open to the use of the public for purposes of vehicular or pedestrian travel.
Lane Line Markings: White pavement marking lines that delineate the separation of
traffic lanes having the same direction of travel on a roadway.
Limited Access: The regulated limitation of public access rights to and from
properties abutting a highway facility. Limited access can be either of the following
types:
Full Limited Access - Provides access to selected public roads and prohibits
crossings at grade and direct driveway connections.
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Local Streets: All streets designated as local on the current District of Columbia
Functional Classification of Streets Map, the latest copy of which is on file with the
Office of Policy and Planning.
Median: The area between two roadways of a divided highway measured from the
edge of traveled way to the edge of traveled way. The median excludes turn lanes.
The median width might be different between intersections, interchanges, and at
opposite approaches of the same intersection.
Motorized Wheelchair: A battery operated chair on wheels, designated for, and used
primarily by a handicapped person, and which is incapable of speed in excess of eight
miles per hour.
Multiple Lanes: Two or more through traffic lanes in any one direction.
MUTCD: The Manual on Uniform Traffic Control Devices, 2003 Edition, Revision 1
published by the U.S. Department of Transportation.
Off-Peak Traffic Hours: All hours of the day and days of the week not defined as
“peak traffic hours.”
Peak Traffic Hours: The hours of 7:00 a.m. to 9:30 a.m. and 4:00 p.m. to 6:30 p.m.
Monday through Friday, except holidays.
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Public Highway: A road, street, alley, or highway in the District open to the public
as a matter of right for the purposes of vehicular traffic.
Raised Pavement Marker: A device with a height of at least 0.4 inches mounted on
or in a road surface and intended to supplement pavement markings.
Regulatory Sign: A sign that gives notice to road users of traffic laws or regulations.
Reversible Lane: A lane in which the direction of travel is reversed during certain
hours in order to increase the capacity in the direction of the heavier traffic demand.
Road User: A vehicle operator, bicyclist, or pedestrian within the highway, including
workers in temporary traffic control zones.
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Sidewalk: That portion of a street between the curb line, or the lateral line of a
roadway, and the adjacent property line or on easements of private property, intended
for use by pedestrians.
Sign: Any traffic control device that is intended to communicate specific information
to road users through a word or symbol legend. Signs do not include traffic control
signals, pavement markings, delineators, or channelization devices.
Sign Assembly: A group of signs, located on the same support(s), which supplement
one another in conveying information to road users.
Sign Illumination: Either internal or external lighting that shows similar color by day
or night. Street, highway, or strobe lighting shall not be considered as meeting this
definition.
Sign Legend: All word messages, logos, and symbol designs that are intended to
convey specific meanings.
Sign Panel: A separate panel or piece of material containing a word or symbol legend
that is affixed to the face of a sign.
Design Speed - a selected speed used to determine the various geometric design
features of a roadway.
Posted Speed - the speed limit determined by law and shown on Speed Limit
signs.
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Speed Limit: The maximum (or minimum) speed applicable to a section of highway as
established by law.
Speed Zone: A section of highway with a speed limit that is established by law but
which may be different from a legislatively specified statutory speed limit.
Stop Line: A solid white pavement marking line extending across approach lanes to
indicate the point at which a stop is intended or required to be made.
Street: A public highway as shown on the record of the District, whether designated as a
street, alley, avenue, freeway, road, drive, lane, place, boulevard, parkway, circle, or by
any other term.
Temporary Traffic Control Zone: Highway segment located between the first and last
advance warning traffic control devices where road user conditions are changed because
of a work zone or incident by the use of temporary traffic control devices, flaggers,
police, or other authorized personnel.
Termination Area: Area used for returning traffic to the normal path.
Traffic: Pedestrians, bicyclists, ridden or herded animals, vehicles, streetcars, and other
conveyances either singularly or together while using any highway for purposes of travel.
Traffic Control Signal (Traffic Signal): Any device, whether manually, electrically, or
mechanically operated, by which traffic is alternately directed to stop and proceed.
Traffic Control Devices: Signs, parking meters, traffic signals, barricades, and/or
channelizing devices existing and/or temporary as defined and/or illustrated in this
Manual and in the Manual on Uniform Traffic Control Devices (MUTCD) used to
regulate, warn, or guide traffic, placed on, over, or adjacent to a street, highway,
pedestrian facility, or bicycle path by authority of a public agency having jurisdiction.
Traffic Lane: Marked pathway, not less than 10 feet wide, for vehicle traffic on streets.
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Traffic Space: Pathway for routing traffic through the temporary traffic control zone.
Transition Area: Areas within the temporary traffic control zone where changes in lane-
use patterns are implemented.
Traveled Way: The portion of the roadway for the movement of vehicles, exclusive of
the shoulders, berms, sidewalks, and parking lanes.
Urban Street: A type of street normally characterized by relatively low speeds, wide
ranges of traffic volumes, narrower lanes, frequent intersections and driveways,
significant pedestrian traffic, and more businesses and houses.
Warning Sign: A sign that gives notice to road users of a situation that might not be
readily apparent.
Weekdays: The days of the week starting at 5:00 a.m. on Monday and ending at
10:00 p.m. on Friday, except holidays.
Weekends: The days of the week starting at 10:00 p.m. on Friday and ending at 5:00
a.m. on Monday.
Wheelchair: A chair on wheels, designated for, and used primarily by, a handicapped
person.
Work Area: The work space or public space set aside for workers, equipment, and
material storage.
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Standard:
The standards presented in this manual are the minimum required. Additional
signs, cones, barricades, and warning devices may be used, but, at no time will less
than what is specified herein be acceptable. Since public safety is involved, a high
degree of conformity to the presented standards is necessary. This Manual is
intended to supplement the MUTCD, which remains the national standard. The
MUTCD should be examined for treatments which are excluded from this Manual.
Support:
Any day declared a holiday by the District shall be observed. When a holiday falls on a
Sunday, the following Monday will be observed as a holiday. When a holiday falls on a
Saturday, the preceding Friday will be observed.
Standard:
When the word messages shown in Table 2-1 need to be abbreviated in connection
with traffic control devices, the abbreviations shown in Table 2-1 shall be used.
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Guidance:
The abbreviations for the words listed in Table 2-2 should not be used in connection with
traffic control devices unless the prompt word shown in Table 2-2 either precedes or
follows the abbreviation.
Standard:
The abbreviations shown in Table 2-3 shall not be used in connection with traffic
control devices because of their potential to be misinterpreted by road users.
Guidance:
Where multiple abbreviations are permitted in Tables 2-1 or 2-2, the same abbreviation
should be used throughout a Ward or single work zone area.
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Table 2-2. Abbreviations That Are Acceptable Only with a Prompt Word
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Standard:
Support:
Construction, maintenance, utility, and incident zones can all benefit from temporary
traffic control to compensate for the unexpected or unusual situations faced by road users.
When planning for temporary traffic control in these zones, it can be assumed that it is
appropriate for road users to exercise caution. Even though road users are assumed to be
using caution, special care is still needed in applying temporary traffic control techniques.
Special plans preparation and coordination with transit, other highway agencies, police
and other emergency units, utilities, schools, and railroad companies might be needed to
reduce unexpected and unusual road user operation situations.
During temporary traffic control activities, commercial vehicles might need to follow a
different route from passenger vehicles because of bridge, weight, clearance, or
geometric restrictions. Also, vehicles carrying hazardous materials might need to follow a
different route from other vehicles.
Experience has shown that following the fundamental principles of this manual will assist
road users and help protect workers in the vicinity of temporary traffic control zones.
While these principles provide guidance for good temporary traffic control for the
practitioner, they do not establish standards and warrants.
Guidance:
The needs of pedestrians who have disabilities should be considered in accordance with
the Americans with Disabilities Act of 1990 (ADA), Title II, Paragraph 35.130. For
further information, see the new accessibility guidelines for buildings and facilities,
transportation facilities, and transportation vehicles, September 1994.
Road user and worker safety in temporary traffic control zones should be an integral and
high-priority element of every project from planning through design and construction.
Similarly, maintenance and utility work should be planned and conducted with the safety
of motorists, bicyclists, pedestrians (including those with disabilities), and workers being
considered at all times.
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If the temporary traffic control zone includes a highway-rail grade crossing, early
coordination with the railroad company should take place.
Support:
Formulating specific plans for temporary traffic control at traffic incidents is difficult
because of the variety of situations that can arise.
Guidance:
1. The basic safety principles governing the design of permanent roadways and
roadsides should also govern the design of temporary traffic control zones. The
goal should be to route road users through such zones using roadway geometrics,
roadside features, and temporary traffic control devices. These devices should be
as close as possible to those for normal highway situations.
Road user movement should be inhibited as little as practical, based on the following
considerations:
1. Temporary traffic control at work and incident sites should be designed on the
assumption that motorists will only reduce their speeds if they clearly perceive a
need to do so (see information on speed control).
3. Provisions should be made for the reasonably safe operation of work, particularly
on high-speed, high-volume roadways.
4. Road users should be encouraged to use alternative routes that do not include
temporary traffic control zones.
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7. Early coordination with officials having jurisdiction over the affected cross
streets and providing emergency services should occur before roadway or ramp
closings.
Motorists, bicyclists, and pedestrians should be guided in a clear and positive manner
while approaching and traversing temporary traffic control zones and incident sites. The
following principles should be applied:
2. Temporary traffic control devices inconsistent with intended travel paths through
temporary traffic control zones should be removed or covered. However, in short
duration and mobile operations, where visible permanent devices are inconsistent
with intended travel paths, devices that highlight or emphasize the appropriate
path should be used.
3. Flagging procedures, when used, should provide positive guidance to road users
traversing the temporary traffic control zone.
To provide acceptable levels of operation, routine day and night inspections of temporary
traffic control elements should be performed.
Standard:
Guidance:
Review of temporary traffic control on high speed, high traffic volume projects should
also be performed during night and non-work periods (weekends), as well on all projects
after severe weather conditions.
Standard:
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control shall be corrected and documented as soon as possible. The review and
documentation of temporary traffic control installation shall be by someone trained
and knowledgeable about the fundamental principles of temporary traffic control
and related work activities being performed. The individual responsible for
temporary traffic control review shall have the authority to halt work until
applicable or remedial safety measures are taken.
Support:
Guidance:
When warranted, an engineering study should be made (in cooperation with law
enforcement officials) of reported crashes occurring within the temporary traffic control
zone. Crash records in temporary traffic control zones should be monitored to identify
the need for changes in the temporary traffic control zone.
Standard:
All temporary traffic control devices shall be removed as soon as practical when
they are no longer needed. When work is suspended for short periods, advance
warning signs that are no longer appropriate shall be removed from the roadway,
and other inappropriate devices shall be removed from the work area so they are
not visible to motorists.
Guidance:
Attention should be given to the maintenance of roadside safety during the life of the
temporary traffic control zone by applying the following principles:
3. Work equipment, workers' private vehicles, materials, and debris should be stored
in such a manner to reduce the probability of being impacted by run-off-the-road
vehicles.
Each person whose actions affect temporary traffic control zone safety, from the upper-
level management through the field workers, should receive training appropriate to the
job decisions each individual is required to make.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Only those individuals who are trained in proper temporary traffic control practices
and have a basic understanding of the principles (established by applicable
standards and guidelines, including those of this Manual) shall supervise the
selection, placement, and maintenance of temporary traffic control devices used for
temporary traffic control zones and for incident management.
Guidance:
1. The need of all road users (motorists, bicyclists, and pedestrians) should be
assessed such that appropriate advance notice is given and clearly defined
alternate paths are provided.
2. The cooperation of the various news media should be sought in publicizing the
existence of and reasons for temporary traffic control zones because news
releases can assist in keeping the road users well-informed.
4. The needs of emergency service providers (police, fire, and medical) should be
assessed and appropriate coordination and accommodations made.
6. The needs of commercial vehicles such as buses and large trucks should be
assessed and appropriate accommodations made.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
3-6
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
With the exception of issuance of a blanket permit, which is acceptable for one year,
Temporary Traffic Control Plans (TTCP) shall be effective for a period of no longer
than six months after approval by DDOT. All work in excess of six months shall
require re-submittal of TTCP.
When applying for a blanket permit, an electronic spreadsheet shall be sent weekly
to TSA and Public Space Management Administration (PSMA) prior to work
commencing.
Support:
Temporary traffic control plans range in scope from being very detailed to simply
referencing typical drawings contained in this Manual, standard approved highway
agency drawings and manuals, or specific drawings contained in the contract documents.
The degree of detail in the temporary traffic control plan depends entirely on the nature
and complexity of the situation.
Guidance:
Traffic control planning should be completed for all highway construction, utility work,
maintenance operations, and incident management including minor maintenance and
utility projects prior to occupying the temporary traffic control zone. Planning for all
road users should be included in the process.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Provisions may be incorporated into the project bid documents that enable contractors to
develop an alternate temporary traffic control plan.
Standard:
This alternate or modified plan shall be reviewed and approved by a trained and
knowledgeable authority in temporary traffic control practices prior to
implementation.
Guidance:
Provisions for effective continuity of transit service should be incorporated into the
temporary traffic control planning process because often public transit buses cannot
efficiently be detoured in the same manner as other vehicles (particularly for short-term
maintenance projects). Where applicable, the temporary traffic control plan should
provide for features such as temporary bus stops, pull-outs, and satisfactory waiting
areas for transit patrons, if applicable (see Section 10A.05 of the MUTCD for additional
light rail transit issues to consider for temporary traffic control).
Reduced speed zoning should be avoided as much as practical. Reduced speed limits
should be used only in the specific portion of the temporary traffic control zone where
conditions or restrictive features are present. However, frequent changes in the speed
limit should be avoided.
A temporary traffic control plan should be designed so that vehicles can safely travel
through the temporary traffic control zone with a speed limit reduction of no more than
10 mph.
Standard:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
A reduction of more than 10 mph in the speed limit should be used only when required by
restrictive features in the temporary traffic control zone. Where restrictive features justify
a speed reduction of more than 10 mph, additional motorist notification should be
provided. The speed limit should be stepped down in advance of the location requiring
the lowest speed, and additional temporary traffic control warning devices should be
used. Regulatory speed signs shall be used within the Work Zone such that the District of
Columbia Metropolitan Police Department can enforce the reduced speed limit. Reduced
speed zoning (lowering the regulatory speed limit) should be avoided as much as
practical because motorists will reduce their speeds only if they clearly perceive a need
to do so.
Support:
Research has demonstrated that large reductions in the speed limit, such as a 25 mph
reduction, on high-speed roadways increase speed variance and the potential for crashes.
Smaller reductions in the speed limit of up to 10 mph cause smaller changes in speed
variance and lessen the potential for increased crashes. A reduction in the regulatory
speed limit of only up to 10 mph from the normal speed limit has been shown to be more
effective.
Support:
A temporary traffic control zone is an area of a highway where road user conditions are
changed because of a work zone or an incident through the use of temporary traffic
control devices, police, or other authorized personnel.
An incident area is an area of a highway where temporary traffic controls are imposed by
authorized officials in response to a traffic incident, natural disaster, or special event. It
extends from the first warning sign or rotating/strobe lights on a vehicle to the last
temporary traffic control device or to a point where road users return to the original lane
alignment and are clear of the incident.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
Most temporary traffic control zones are divided into five areas: the advance warning
area, the transition area, the buffer space area, the activity area, and the termination area.
Figure 4-1 illustrates these five areas. These five areas are described in the sections that
follow.
Support:
The advance warning area is the section of highway where road users are informed about
the upcoming work zone or incident area.
Option:
The advance warning area may vary from a single sign or rotating/strobe lights on a
vehicle to a series of signs in advance of the temporary traffic control zone activity area.
Guidance:
Typical distances for placement of advance warning signs on expressways and freeways
should be longer because motorists are conditioned to uninterrupted flow. Therefore the
advance warning sign placement should extend on these facilities as far as one mile or
more.
Option:
Low speed urban streets with speeds of 25 mph or less may reduce the spacing to +/-150’
between signs.
4-4
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
END
ROAD WORK
Termination Area
lets traffic resume
normal driving
Work Area
set aside for
workers, equipment,
Buffer Area (lateral) and material storage
provides protection for
traffic and workers Activity Area
is where work
takes place
Buffer Area (longitudinal)
provides protection for
traffic and workers
Transition Area
moves traffic out
of its normal path
ROAD
WORK
AHEAD
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
The transition area is that section of highway where road users are redirected out of their
normal path.
Standard:
When redirection of the road users’ normal path is required, they shall be
channelized from the normal path to a new path.
Support:
In mobile operations, the transition area moves with the work space. Transition areas
usually involve strategic use of tapers, which because of their importance, are discussed
separately in detail.
Support:
The buffer space is a lateral and/or longitudinal area that separates road user flow from
the work space or an unsafe area and might provide some recovery space for an errant
vehicle. The traffic space is the portion of the highway in which road users are routed
through the activity area.
Standard:
Neither work activity nor storage of equipment, vehicles, or material shall occur
within a buffer space.
Option:
Buffer spaces may be positioned either longitudinally or laterally with respect to the
direction of road user flow. The activity area may contain one or more lateral or
longitudinal buffer spaces.
Guidance:
The length of a longitudinal buffer space should be as shown in Table 4-1, and is based
on the posted speed limit of the temporary traffic control zone.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Speed Distance
(mph) (ft)
20 35
25 55
30 85
35 120
40 170
45 220
50 280
55 335
60 415
65 485
Support:
Typically, the buffer space is formed as a traffic island and defined by channelizing
devices. When a shadow vehicle is placed in advance of the work space, only the space
upstream of the vehicle constitutes the buffer space.
Option:
The lateral buffer space may be used to separate the traffic space from the work space, as
shown in Figures 4-1 and 4-2, or such areas as excavations or pavement-edge drop-offs.
A lateral buffer space also may be used between two travel lanes, especially those
carrying opposing flows.
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Guidance:
If used, an incident response and emergency-vehicle storage area should not extend into
any portion of the buffer space.
Support:
The activity area is the section of the highway where the work activity takes place.
The work space is that portion of the highway closed to road users and set aside for
workers, equipment, and material and a shadow vehicle if one is used upstream. Work
spaces are usually delineated for road users by channelizing devices or, to exclude
vehicles and pedestrians, by temporary barriers.
Option:
Guidance:
Since there may be several work spaces (some even separated by several miles) within
the project limits, each work space should be adequately signed to inform road users and
reduce confusion.
The maximum length of the work space should not exceed two miles unless approved by
the DDOT Engineer.
Support:
The traffic space is the portion of the highway in which road users are routed through the
activity area.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
The termination area shall be used to return road users to their normal path. The
termination area shall extend from the downstream end of the work area to the
END ROAD WORK signs.
An END ROAD WORK sign, a Speed Limit sign, or other signs shall be used to
inform road users that they can resume normal operations.
Guidance:
Conditions may exist where posting the END ROAD WORK signs may not be helpful. For
example, the END ROAD WORK signs should normally not be used if other temporary
traffic control zones begin within a quarter-mile of the temporary traffic control within
the urban core.
4.4 TAPERS
Guidance:
Option:
Support:
Tapers are created by using a series of channelizing devices and/or pavement markings to
move traffic out of or into the normal path. Types of tapers are shown in Figure 4-2.
Longer tapers are not necessarily better than shorter tapers (particularly in the urban core
characterized by short block lengths and driveways) because extended tapers tend to
encourage sluggish operation and to encourage motorists to delay lane changes
unnecessarily. The test concerning adequate lengths of tapers involves observation of
motorist performance after temporary traffic control plans are put into effect.
Guidance:
The criteria for determining the taper length (L) are shown in Table 4-2 and should be
the minimum used.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
The maximum distance in feet between devices in a taper should not exceed 20 feet at
speeds up to 35 mph and 40 feet for speeds greater than 35 mph.
Table 4-2. Taper Length Criteria for Temporary Traffic Control Zones
Support:
A merging taper requires the longest distance because motorists are required to merge
into common road space.
Guidance:
A merging taper should be long enough to enable merging motorists to have adequate
advance warning and sufficient length to adjust their speeds and merge into a single lane
before the end of the transition.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
A shifting taper is used when a lateral shift is needed. When more space is available, a
longer than minimum taper distance can be beneficial. Changes in alignment can also be
accomplished by using horizontal curves designed for normal highway speeds.
Guidance:
A shifting taper should have a minimum length of at least one-half L (Table 4-3).
Support:
A shoulder taper will be beneficial on a high-speed roadway where shoulders are part of
the activity area and are closed or when improved shoulders might be mistaken as a
driving lane. In these instances, the same, but abbreviated, closure procedures used on a
normal portion of the roadway can be used.
Guidance:
Type of Taper
50 feet min
Two-way Traffic Taper Opposing directions
100 feet max
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
When used, a downstream taper should have a minimum length of approximately 100 feet
per lane with devices placed at a spacing of approximately 20 feet.
Support:
The one-lane, two-way taper is used in advance of an activity area that occupies part of a
two-way roadway in such a way that a portion of the road is used alternately by traffic in
each direction.
Guidance:
Support:
Guidance:
Detours should be clearly signed over their entire length so that road users can easily
use existing highways to return to the original highway.
Support:
Standard:
When traffic in both directions must use a single lane for a limited distance,
movements from each end shall be coordinated.
Guidance:
Provisions should be made for alternate one-way movement through the constricted
section via methods such as flagger control, a flag transfer, a pilot car, or traffic control
signals.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Control points at each end should be chosen to permit easy passing of opposing lanes of
vehicles. If traffic on the affected one-lane roadway is not visible from one end to the
other, then flagging procedures, a pilot car, or traffic control signal should be used to
control opposing traffic flows.
Support:
At a spot constriction, such as an isolated pavement patch on highways with lower speeds
and adequate sight distance, the movement of traffic through one-lane, two-way
constrictions tends to be self-regulating.
Option:
When a one-lane, two-way temporary traffic control zone is short enough to allow a
flagger to see from one end of the zone to the other, traffic may be controlled by either a
single flagger or by a flagger at each end of the section.
Guidance:
When a single flagger is used, the flagger should be stationed on the shoulder opposite
the constriction or work space or in a position where good visibility and traffic control
can be maintained at all times. When good visibility and traffic control cannot be
maintained by one flagger station, traffic should be controlled by a flagger at each end of
the section. One of the flaggers should be designated as the coordinator.
Option:
A pilot car may be used to guide a queue of vehicles through the temporary traffic control
zone or detour.
Guidance:
The operation of the pilot vehicle should be coordinated with flagging operations or
other controls at each end of the one-lane section. The pilot car should have the name of
the contractor or contracting authority prominently displayed.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Option:
Traffic control signals may be used to control motor vehicle traffic movements in one-
lane, two-way temporary traffic control zones on a case-by-case basis, as approved by
Traffic Services Administration (DDOT) (see Chapter 4G of the MUCTD).
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
4-16
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
The various temporary traffic control provisions for pedestrian and worker safety
set forth in this Manual and the MUTCD shall be applied by knowledgeable (for
example, trained and/or certified) persons after appropriate evaluation and
engineering judgment. Advance notification of sidewalk closures shall be required
and is subject to approval by DDOT prior to implementation.
Standard:
Guidance:
Some major considerations in planning for pedestrian safety in work zones include:
A. Pedestrians should not be led into conflicts with work site vehicles, equipment,
and operations.
B. Pedestrians should not be led into conflicts with work site vehicles moving
through or around the work site.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
It must be recognized that pedestrians are reluctant to retrace their steps to a prior
intersection for a crossing or to add distance or out-of-the-way travel to a destination.
Guidance:
A. Pedestrians should not be led into conflicts with work site vehicles, equipment,
and operations.
B. Pedestrians should not be led into conflicts with vehicles moving through or
around the work site.
A pedestrian route should not be severed and/or moved for non-construction activities
such as parking for vehicles and equipment. Consideration should be made to separate
pedestrian movements from both work site activity and motor vehicle traffic. Pedestrians
should be appropriately directed with advance signing that encourages them to cross to
the opposite side of the roadway. In urban and suburban areas with high motor vehicle
traffic volumes, these signs should be placed at intersections so that pedestrians are not
confronted with midblock work sites that will induce them to attempt skirting the work
site or making a midblock crossing.
Figures 5-1 and 5-2 show typical temporary traffic control device usage and techniques
for pedestrian movement through work zones.
5-2
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
CROSSWALK CLOSED
(OPTIONAL)
CROSSWALK
PEDESTRIAN
CROSSWALK
PEDESTRIAN
CROSSWALK CLOSED
USE OTHER SIDE
TEMPORARY
MARKINGS FOR
CROSSWALK
LINES (CROSS
HATCHING
OPTIONAL)
SIDEWALK CLOSED
CROSS HERE
AHEAD
WORK
ROAD
SIDEWALK
CLOSED
SIDEWALK CLOSED
AHEAD
CROSS HERE
ROAD
WORK
AHEAD
5-3
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
END END
ROAD WORK ROAD WORK
CLOSED
SIDEWALK
PEDESTRIANS
SIDEWALK
CLOSED PEDESTRIANS
SIDEWALK CLOSED
CROSS HERE
CURB
LANE
CLOSED
AHEAD
ROAD
WORK
AHEAD ROAD
WORK
AHEAD
5-4
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
The following items must be considered when creating a Traffic Control Plan
(TCP):
Guidance:
Option:
Whenever it is feasible, closing off the work site from pedestrian intrusion may be
preferable to channelizing pedestrian traffic along the site with temporary traffic control
devices such as barricades and drums or other suitable fencing.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
Fencing should not create sight distance restrictions for road users. Fences should not be
constructed of materials that would be hazardous if impacted by vehicles. Wooden
railing, fencing, and similar systems placed immediately adjacent to motor vehicle traffic
should not be used as substitutes for crashworthy temporary traffic barriers.
Standard:
Temporary traffic control devices used to delineate a temporary traffic control zone
pedestrian walkway shall be crashworthy and, when struck by vehicles, present a
minimum threat to pedestrians, workers, and occupants of impacting vehicles.
Guidance:
Ballast for temporary traffic control devices should be kept to the minimum amount
needed and should be mounted low to prevent penetration of the vehicle windshield.
Movement by work vehicles and equipment across designated pedestrian paths should be
minimized and, when necessary, should be controlled by flaggers or temporary traffic
control. Staging or stopping of work vehicles or equipment along the side of pedestrian
paths should be avoided, since it encourages movement of workers, equipment, and
materials across the pedestrian path. Access to work space across pedestrian walkways
should be minimized because the access often creates unacceptable changes in grade and
rough or muddy terrain, and pedestrians will tend to avoid these areas by attempting
non-intersection crossings.
Standard:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
5-7
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
5-8
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
D. Small trailers can be placed on top of the covered walkway provided the
covered walkway can support the weight.
E. Minimum requirements for the floor and roof shall be 300 pounds per square
foot. The walking surface shall be paved or covered with plywood or wood
planking.
F. The overhead clearance shall be at least eight feet high. Temporary covered
ways shall afford free passage of at least six feet in width along the sidewalk.
G. Continuous handrails shall be installed along the walls of the covered
walkway to aid pedestrians with usual and ambulatory difficulties.
H. Adequate provisions shall be made for persons with disabilities, including
wheelchair ramps.
I. Covered pedestrian pathways shall be provided with corner treatments
which allow a minimum 45-foot sight distance triangle.
Standard:
Support:
Depending on the possible motor vehicle speed and angle of impact, temporary traffic
barriers might deflect upon impact by an errant vehicle.
Standard:
Short intermittent segments of temporary traffic barrier shall not be used because
they nullify the containment and redirective capabilities of the temporary traffic
barrier, increase the potential for serious injury both to vehicle occupants and
pedestrians, and encourage the presence of blunt, leading ends. All upstream
leading ends that are present shall be appropriately flared or protected with
properly installed and maintained crashworthy cushions. Adjacent temporary
traffic barrier segments shall be properly connected in order to provide the overall
strength required for the temporary traffic barrier to perform properly.
Normal vertical curbing shall not be used as a substitute for temporary traffic
barriers when temporary traffic barriers are clearly needed.
Option:
5-9
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
also be used to inhibit conflicts with motor vehicle traffic by minimizing the possibility
of midblock crossings.
Support:
A major concern for pedestrians is urban and suburban building construction encroaching
onto the contiguous sidewalks, which forces pedestrians off the curb into direct conflict
with moving vehicles.
Guidance:
If a high potential exists for vehicle incursions into the pedestrian path, pedestrians
should be rerouted or temporary traffic barriers should be installed.
Support:
Standard temporary traffic control devices can satisfactorily delineate a pedestrian path.
Although tape, rope, fencing, or plastic chain strung between devices can help discourage
pedestrian movements off the designated pathway, they cannot eliminate them entirely.
Guidance:
The extent of pedestrian needs should be determined through engineering judgment for
each work zone situation. The contractor in charge of the temporary traffic control
should regularly inspect the activity area so that effective pedestrian temporary traffic
control is maintained.
Support:
Equally as important as the safety of road users traveling through the temporary traffic
control zone is the safety of workers. Temporary traffic control zones present temporary
and constantly-changing conditions that are unexpected by the road user. This creates an
even higher degree of vulnerability for workers on or near the roadway. Maintaining
temporary traffic control zones with road user flow inhibited as little as possible and
using temporary traffic control devices that get the road user's attention and provide
positive direction are of particular importance.
Guidance:
The following are the key elements of temporary traffic control management that should
be considered to improve worker safety:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
A. Training - All workers should be trained on how to work next to motor vehicle
traffic in a way that minimizes their vulnerability. Workers having specific
temporary traffic control responsibilities should be trained in temporary
traffic control techniques, device usage, and placement. Training should be
conducted on a continual basis.
B. Worker Clothing - All workers should be adequately clothed for the type of
operations they will be performing (See standard below for clothing
requirement when working near traffic).
C. Temporary Traffic Barriers - Temporary traffic barriers should be placed
along the work space based on an engineering study considering factors such
as lateral clearance of workers from adjacent traffic, speed of traffic, duration
and type of operations, time of day, and volume of traffic.
D. Speed Reduction - Reducing the speed of motor vehicle traffic, mainly through
regulatory speed zoning, funneling, use of law enforcement officials, lane
reduction, or flaggers should be considered.
E. Activity Area – Planning the internal work activity area to minimize backing-
up maneuvers of construction vehicles should be considered to minimize the
inherent risk to workers on foot.
Standard:
After January 1, 2007, workers shall wear safety apparel meeting the requirements
of ISEA “American National Standard for High-Visibility Apparel” (see MUTCD
Section 1A.11 “Relation to Other Publications”) and labeled as meeting the
ANSI/ISEA 107-2004 standard performance for Class 3 risk exposure. The apparel
background (outer) material shall be either fluorescent orange-red or fluorescent
yellow-green as defined in the standard. The retroreflective material shall either be
orange, yellow, white, silver, yellow-green, or a fluorescent version of these colors,
and shall be visible at a minimum distance of 1,000 feet. The retroreflective clothing
shall be designed to clearly identify the wearer as a person.
Guidance:
Until January 1, 2007, all workers should wear an orange, yellow, or yellow-green (or
fluorescent versions of these colors) shirt, vest, or jacket for daytime work visible at a
minimum distance of 1,000 feet.
Standard:
For nighttime work outside garments similar to daytime garments shall be worn
and shall be retroreflective. The retroreflective material shall be orange, yellow,
white, silver, yellow-green, or a fluorescent version of one of these colors and shall
be visible at a minimum distance of 1,000 feet. The retroreflective clothing shall be
designed to clearly identify the wearer as a person.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
The following are additional elements of temporary traffic control management that may
be considered to improve worker safety:
1. Road Closure - If alternate routes are available to handle road users, the road
may be closed temporarily. This may also facilitate project completion and
thus further reduce worker vulnerability.
2. Police Use - In highly vulnerable work situations, particularly those of
relatively short duration, police units may be stationed to heighten the
awareness of passing vehicular traffic and to improve safety through the
temporary traffic control zone.
3. Lighting - For nighttime work, the temporary traffic control zone and
approaches may be lighted.
4. Special Devices - These include rumble strips, portable changeable message
signs, hazard identification beacons, flags, and warning lights. Intrusion
warning devices may be used to alert workers to the approach of errant
vehicles.
Support:
Judicious use of the special devices described in Item 4 above might be helpful for
certain difficult temporary traffic control situations, but misuse or overuse of special
devices or techniques might lessen their effectiveness.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
A flagger shall be a person who provides temporary traffic control. A flagger shall
be certified in flagging and shall have his/her certification card with them at all
times while performing flagging activities.
Guidance:
Because flaggers are responsible for public safety and make the greatest number of
contacts with the public of all highway workers, they should be trained in safe traffic
control practices and public contact techniques. Flaggers should have the following
minimum qualifications, skills, and abilities:
A. Sense of responsibility for the safety of the public and the workers
B. Adequate training in safe temporary traffic control practices
C. Average intelligence
D. Good physical condition, including sight, mobility, and hearing
E. Mental alertness and the ability to react in an emergency
F. Courteous but firm manner
G. Skill in communicating specific instructions clearly, firmly, and courteously
H. At least 18 years old
Standard:
The flagger shall remain fully clothed, from neck to feet, when flagging. This
includes the wearing of shirts with sleeves (at least short sleeves in length), long
pants, OSHA approved hardhats, and steel toe safety shoes. Prior to July 1, 2007,
for daytime work, the flagger's vest and/or jacket shall be orange, yellow, yellow-
green, or a fluorescent version of these colors. The vest or jacket must be approved
by DDOT. For nighttime work, similar outside garments shall be retroreflective.
The retroreflective material shall be orange, yellow, white, silver, yellow-green, or a
fluorescent version of these colors, and shall be visible at a minimum distance of
1,000 feet. The retroreflective clothing shall be designed to clearly identify the
wearer as a person.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
After January 1, 2007, flaggers shall wear safety apparel meeting the requirements
of ISEA “American National Standard for High-Visibility Apparel” and labeled as
meeting the ANSI/ISEA 107-2004 standard performance for Class 3 risk exposure.
The apparel background (outer) material shall be either fluorescent orange-red or
fluorescent yellow-green as defined in the standard. The retroreflective material
shall be orange, yellow, white, silver, yellow-green, or a fluorescent version of these
colors, and shall be visible at a minimum distance of 1,000 feet. The retroreflective
clothing shall be designed to clearly identify the wearer as a person.
Guidance:
The flagger should be properly attired such that they are not distracting to motorists (no
provocative clothing or clothing with words or phrases unrelated to work zone
operation).
When uniformed law enforcement officers are used, high-visibility clothing as described
above should be worn by the law enforcement officer.
Support:
Hand-signaling devices, such as STOP/SLOW paddles, lights, and red flags, are used to
control road users through temporary traffic control zones.
Standard:
The STOP/SLOW paddle shall be the primary hand-signaling device because the
STOP/SLOW paddle gives road users more positive guidance than red flags.
Guidance:
Use of red flags should be limited to emergency situations and use by traffic spotters.
Standard:
6-2
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
A. Two white lights centered vertically above and below the STOP and/or SLOW
legend
B. Two white lights centered horizontally on each side of the STOP and/or SLOW
legend
C. One white light centered below the STOP and/or SLOW legend
D. A series of eight or more small white lights no larger than 1/4 inch in diameter
along the outer edge of the paddle, arranged in an octagonal pattern at the eight
corners of the border of the STOP side of the paddle and/or arranged in a diamond
pattern along the border of the SLOW side of the panel. More than eight lights
may be used only if the arrangement of the lights is such that it clearly conveys
the octagonal shape of the STOP side of the paddle and/or the diamond shape of
the SLOW side of the paddle
Standard:
If flashing lights are used on the STOP/SLOW paddle, the flash rate shall be at
least 50, but not more than 60, flashes per minute. Flags, when used for emergency
situations and by traffic spotters, shall be a minimum of 24 inches square, made of a
good grade of red material, and securely fastened to a staff that is approximately
36 inches in length. When used at nighttime, flags shall be retroreflectorized red.
Option:
For surveying and other operations occurring on the road edge or near the centerline of
two-lane roadways, a combination STOP/SLOW paddle and SLOW/SLOW paddle
utilizing a double-sided SLOW flip panel may be used to prevent unnecessary stopping
of vehicles by the flagger.
Support:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
To Stop Traffic
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
A. To stop road users, the flagger shall face road users and aim the STOP
paddle face toward road users in a stationary position with the arm extended
horizontally away from the body. The free arm shall be held with the palm of
the hand above shoulder level toward approaching traffic.
B. To direct stopped road users to proceed, the flagger shall face road users
and aim the SLOW paddle face toward road users in a stationary position
with the arm extended horizontally away from the body. The flagger shall
motion with the free hand for road users to proceed.
C. To alert or slow traffic, the flagger shall face road users with the SLOW
paddle face aimed toward road users in a stationary position with the arm
extended horizontally away from the body. For added emphasis, the flagger
may raise and lower the free hand with the palm down.
Option:
To further alert or slow traffic, the flagger holding the SLOW paddle face toward road
users may motion up and down with the free hand, palm down.
Standard:
A. To stop road users, the flagger shall face road users and extend the flag staff
horizontally across the road users’ lane in a stationary position so that the
full area of the flag is visibly hanging below the staff. The free arm shall be
held with the palm of the hand above the shoulder level toward approaching
traffic.
B. To direct stopped road users to proceed, the flagger shall stand parallel to
the road user movement with flag and arm lowered from the view of the road
users and shall motion with the free hand for road users to proceed. Flags
shall not be used to signal road users to proceed.
C. The flagger shall face traffic with the flag held in the down position and
slowly motion up and down with the free hand, palm down, indicating the
vehicle should slow down.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Flagger stations shall be located far enough in advance of the work space so that
approaching road users will have sufficient distance to stop before entering the
work space. Flagger stations shall be located such there is high visibility for on-
coming traffic.
Support:
Guidelines for determining the distance of the flagger station in advance of the work
space are shown in Table 6-1.
Option:
The distances shown in Table 6-1 may be increased for downgrades and other conditions
that affect stopping distance.
Guidance:
To assure that a fully alert flagger is present at the flagger station, flaggers should be
relieved every two hours for a minimum period of 15 minutes.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Guidance:
The flagger should stand either on the curb or shoulder adjacent to the road user being
controlled or in the closed lane prior to stopping road users. A flagger should only stand
in the lane being used by moving road users AFTER road users have stopped. The
flagger should be clearly visible to the first approaching road user at all times. The
flagger also should be visible to other road users. The flagger should be stationed
sufficiently in advance of the workers to warn them (for example, with audible warning
devices such as horns, whistles, etc.) of approaching danger by out-of-control vehicles.
Standard:
The flagger shall stand alone, never permitting a group of workers to congregate
around the flagger station. Vehicles and equipment shall not be allowed around the
flagger station, which can interfere with the visibility of the flagger to approaching
motorists.
When the flagger is no longer at the flagger station performing flagging duties, the
advance warning signs advising of flagging operations shall be removed.
Option:
If work and/or equipment is still in the area, the ROAD WORK AHEAD sign may
remain.
At a spot constriction, the flagger may have to take a position on the curb or shoulder
opposite the closed section in order to operate effectively.
At spot lane closures where adequate sight distance and a low traffic volume is available
for the safe handling of traffic, the use of one flagger may be sufficient.
Standard:
All flagger stations shall be in communication with each other via electronic
communication equipment (2-way radios, cell-phones with direct connection, etc.).
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
A traffic spotter’s primary function is to alert and assist motorists through temporary
traffic control zones in emergency situations only.
Standard:
Guidance:
The location of the traffic spotter should be where he is visible and capable of directing
traffic from both directions.
Standard:
The ROAD WORK AHEAD sign shall be the minimum sign requirement for traffic
spotters.
Option:
Additional signing and other traffic control devices may be required, depending on the
type and visibility of the operation, subject to the discretion of DDOT.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Traffic control devices shall be defined as all signs, signals, markings, and other
devices used to regulate, warn, or guide traffic, placed on, over, or adjacent to a
street, highway, pedestrian facility, or bikeway by authority of a public body or
official having jurisdiction.
All traffic control devices used on street and highway construction, maintenance,
utility, or incident management operations shall conform to the applicable
provisions of this Manual.
Guidance:
The design and application of temporary traffic control devices used in temporary traffic
control zones should consider the needs of all road users (motorists, pedestrians, and
bicyclists).
Support:
Support:
Temporary traffic control zone signs convey both general and specific messages by
means of words or symbols and have the same three categories as all road user signs:
regulatory, warning, and guide.
Standard:
The colors for regulatory signs shall follow the standards for regulatory signs in
Table 2A-4 and Chapter 2B of the MUTCD. Warning signs in temporary traffic
control zones shall have a black legend on a fluorescent orange background, except
for the Railroad Advance Warning (W10-1) sign, which shall have a black message
and border on a yellow background. Colors for guide signs shall follow the
Standards in Table 2A-4 and Chapter 2D, except for guide signs as noted in Section
6F.47 of the MUTCD. Sign material shall conform to the latest District Road and
Bridge Specification including all revisions to such.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Existing warning signs that are still applicable may remain in place.
Standard orange flags or flashing warning lights for post-mounted signs may be used in
conjunction with signs.
Standard:
When standard orange 24 x 24 inches flags or flashing warning lights are used in
conjunction with post mounted signs, they shall not block the sign face.
Option:
The dimensions of signs shown in this Manual are for standard sizes, which may be
increased wherever necessary for greater legibility or emphasis.
Standard:
Support:
Standard:
All signs used at night shall be either retroreflective with a material that has a
smooth, sealed outer surface or illuminated to show the same shape and similar
color both day and night.
Option:
Support:
Street, highway, or strobe lighting does not constitute external sign illumination.
Option:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
Signs should be located on the right side of the roadway unless otherwise specified in this
Manual.
Standard:
On roadways having a median wider than eight feet, left and right sign assemblies
shall be used.
Option:
Support:
Guidelines for height and lateral clearance of temporary post-mounted signs are shown in
Figure 7-1.
Standard:
Post-mounted signs installed at the side of the road in residential and urban areas
shall be mounted at a height at least seven feet, measured from the bottom of the
sign to the near edge of the pavement. For crashworthy purposes, the top of the sign
shall be a minimum of nine feet above the ground elevation at the base of the sign.
The height to the bottom of a secondary sign mounted below another sign may be
one foot less than the 7-foot requirement. Signs mounted on barricades and
barricade/sign combinations shall be crashworthy.
For sign posts which are not fixed in the ground, but instead mounted on horizontal
support platforms, sand bags shall be used for ballast to prevent overturning.
Guidance:
Neither portable nor permanent sign supports should be located on sidewalks, bicycle
lanes, or areas designated for pedestrian or bicycle traffic. Signs mounted lower than
seven feet should not project more than four inches into pedestrian facilities.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Signs shall be post-mounted on fixed supports for any work that occurs for a
duration of more than three consecutive days (72 hours).
Guidance:
For operations that occur for a duration of less than three consecutive days (72 hours),
portable spring-loaded sign supports should be used.
Standard:
Sign supports shall be crashworthy. Large signs having an area exceeding 50 square
feet that are installed on multiple breakaway posts shall be mounted a minimum of
seven feet above the ground.
Portable sign supports shall meet the following conditions: accommodate signs of all
standard shapes; including octagonal and triangular; have a flag holder which will
accommodate two flags as an integral part of the unit; have adjustable legs capable
of adjusting to uneven surfaces; and while supporting a 16 square foot rigid sign
panel, the sign support shall be spring loaded and shall withstand 50 mph winds
without tipping over or rotating more than five degrees about its vertical axis
without the use of tie downs or ballast of any kind. The complete unit shall not
exceed 40 pounds. The unit shall meet NCHRP 350 crashworthy standards.
Signs mounted on portable supports shall be no less than one foot above the traveled
way from the bottom of the sign.
Guidance:
For mobile operations, a sign should be mounted on a work vehicle, a shadow vehicle, or
on the shoulder stationed in advance of the temporary traffic control zone or moving
along with it.
Guidance:
Sign posts placed in the clear zone should yield or break away upon impact to minimize
obstructions to road users and to not present an undue risk to workers.
Support:
Depending upon the crash tested design, slight variations to the support might not be
considered crashworthy.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
These supports should meet the breakaway requirements for permanent installations
discussed in the AASHTO Roadside Design Guide.
Option:
The R9-8 through R9-11a series, R11 series, W1-6 through W1-8 series, M4-10, E5-1, or
other similar type signs may be used on portable supports for longer than three days.
Support:
Methods of mounting signs other than on posts are illustrated in Figure 6F-2 of the
MUTCD.
Guidance:
Signs mounted on Type III barricades should not cover more than 50 percent of the top
two rails or 33 percent of the total area of the three rails.
Support:
Signs used in temporary traffic control zones are moved frequently, loaded and unloaded
from trucks, and in general receive much harsher treatment than permanent signs. For this
reason, particular attention must be given to maintaining signs properly for cleanliness,
visibility, and correct positioning.
Standard:
Signs shall be properly maintained for cleanliness, visibility, and correct positioning.
Signs that have lost significant legibility shall be promptly replaced in accordance
with the American Traffic Safety Service Association (ATSSA)’s Quality Standards
for Work Zone Traffic Control Devices.
Support:
Regulatory signs such as those shown in Figures 7-2 and 7-3 inform road users of traffic
laws or regulations and indicate the applicability of legal requirements that would not
otherwise be apparent.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Regulatory signs impose legal obligations on all motorists, and they shall be
authorized by the DDOT Engineer or an official having jurisdiction and conform to
Chapter 2B of the MUTCD.
Standard:
Temporary traffic control regulatory signs shall conform to the Standards for
Regulatory Signs presented in Part 2 of the MUTCD and in the FHWA’s “Standard
Highway Signsiv” book.
Support:
Regulatory signs are generally rectangular with a black legend and border on a white
background. Exceptions include the STOP, YIELD, DO NOT ENTER, WRONG WAY,
and ONE WAY signs.
Option:
The ONE WAY sign may be either a horizontal or vertical rectangular sign.
Standard:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
For all roads functionally classified as minor arterials or below, Advance Warning
Sign shall carry the legend of “XX Blocks” or “XX Feet,” or a legend deemed
necessary by the DDOT Engineer, in advance of the work zone.
Guidance:
The ROAD (STREET) CLOSED (R11-2) sign should be used when the roadway is closed
to all road users except contractors' equipment or officially authorized vehicles. The
R11-2 sign should be accompanied by appropriate warning and detour signing.
Option:
The words BRIDGE OUT (or BRIDGE CLOSED) may be substituted for ROAD
(STREET) CLOSED where applicable.
Guidance:
The ROAD (STREET) CLOSED sign should be installed at or near the center of the
roadway on or above a Type III barricade that closes the roadway.
Standard:
The ROAD (STREET) CLOSED sign shall not be used where road user flow is
maintained or where the actual closure is some distance beyond the sign.
Guidance:
The LOCAL TRAFFIC ONLY (R11-3a, R11-4) signs should be used where road user flow
detours to avoid a closure some distance beyond the sign but where local road users can
use the roadway to the point of closure. Appropriate warning and detour signing should
accompany these signs.
In residential applications, the Local Traffic Only sign should have the legend ROAD
CLOSED XX BLOCKS (OR XX FEET) AHEAD, LOCAL TRAFFIC ONLY (R11-3a).
Option:
In urban areas, the legend ROAD (STREET) CLOSED TO THRU TRAFFIC (R11-4) or
ROAD CLOSED, LOCAL TRAFFIC ONLY may be used.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
The words BRIDGE OUT (or BRIDGE CLOSED) may be substituted for the words
ROAD (STREET) CLOSED on the R11-3a or R11-4 sign where applicable.
Standard:
The sign shall carry the legend ROAD CLOSED [XX] BLOCKS (OR XX FEET)
AHEAD - LOCAL TRAFFIC ONLY or, optionally for urban use, ROAD
(STREET) CLOSED TO THRU TRAFFIC.
WEIGHT LIMIT signs (R12-1, R12-2, R12-5), which shows the gross weight or axle
weight that is permitted on the roadway or bridge, shall be consistent with District
or local regulations and shall not be installed without the approval of the authority
having jurisdiction over the highway.
When weight restrictions are imposed, a marked detour shall be provided for
vehicles weighing more than the posted limit.
Option:
A STAY IN LANE (R4-9) sign may be used where a multilane shift has been
incorporated as part of the temporary traffic control on a highway to direct road users
around road work that occupies part of the roadway on a multilane highway.
Guidance:
SIDEWALK CLOSED signs (R9-9, R9-10, R9-11, R9-11a) should be used where
pedestrian flow is restricted or rerouted by work activities.
The SIDEWALK CLOSED (R9-9) sign should be installed at the beginning of the closed
sidewalk area on both sides of the work zone.
The SIDEWALK CLOSED, (ARROW) USE OTHER SIDE (R9-10) sign should be
installed at the beginning of the restricted sidewalk when a parallel sidewalk exists on the
other side of the roadway.
The SIDEWALK CLOSED AHEAD, (ARROW) CROSS HERE (R9-11) sign should be
used to indicate to pedestrians that sidewalks beyond the sign are closed and to direct
them to open crosswalks, sidewalks, or other travel paths.
The SIDEWALK CLOSED, (ARROW) CROSS HERE (R9-11a) sign should be installed
just beyond the point to which pedestrians are being redirected.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
These signs are typically mounted on a 4-foot wide barricade to encourage compliance.
Option:
Special regulatory signs may be used based on engineering judgment consistent with
regulatory requirements.
Guidance:
Special regulatory signs should conform to the general requirements of color, shape, and
alphabet size and series. The sign message should be brief, legible, and clear.
Support:
Temporary Traffic Control (TTC) zone warning signs (see Figure 7-4) notify road users
of specific situations or conditions on or adjacent to a roadway that might not otherwise
be apparent.
Standard:
TTC warning signs shall conform to the Standards for warning signs presented in
Part 2 of the MUTCD and in FHWA’s “Standard Highway Signs” book (see Section
1A.11). Except as noted in the Option below, TTC warning signs shall be diamond-
shaped with a black legend and border on an orange background, except for the
W10-1 sign, which shall have a black legend and border on a yellow background,
and except for signs that are permitted in Parts 2 or 7 of the MUTCD to have
fluorescent yellow-green backgrounds.
Option:
Warning signs used for TCC incident management situations may have a black legend
and border on a fluorescent pink background.
Mounting or space considerations may justify a change from the standard diamond shape.
In emergencies, available warning signs having yellow backgrounds may be used if signs
with orange or fluorescent pink backgrounds are not on hand.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
Where roadway or road user conditions require greater emphasis, larger than standard
size warning signs should be used, with the symbol or legend enlarged approximately in
proportion to the outside dimensions.
Where any part of the roadway is obstructed or closed by work activities or incidents,
advance warning signs should be installed to alert road users well in advance of these
obstructions or restrictions.
Where road users include pedestrians, the provision of supplemental audible information
or detectable barriers or barricades should be considered for people with visual
disabilities.
Support:
Option:
Standard:
Because of their importance, advance warning signs for higher-speed locations shall
have a size of 48 x 48 inches (see Part 2 of the MUTCD). For freeways and
expressways, the size of diamond-shaped TTC warning signs shall be a minimum of
48 x 48 inches.
Option:
Where speeds and volumes are moderately low, a minimum size of 36 x 36 inches may
be used for advance warning signs.
On low-volume / low-speed roads or on residential City streets where speeds are very
low, signs smaller than the standard size, but not less than 24 x 24 inches, may be used
for warning signs having short word messages or clear symbols.
Advance warning signs larger than the minimum standards may be used for additional
emphasis of the TTC zone (see Part 2 of the MUTCD).
Where distances are not shown on warning signs as part of the message, a supplemental
plaque with the distance legend may be mounted immediately below the sign on the same
support.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
Where highway conditions permit, warning signs should be placed in advance of the TTC
zone at varying distances depending on roadway type, condition, and posted speed.
Where a series of two or more advance warning signs is used, the closest sign to the TTC
zone should be placed approximately 100 feet for low-speed urban streets to 1,000 feet or
more for freeways and expressways.
Support:
Various conditions, such as limited sight distance or obstructions that might require a
motorist to reduce speed or stop, might require additional advance warning signs.
Option:
As an alternative to a specific distance on advance warning signs, the word AHEAD may
be used.
Support:
At TTC zones on lightly-traveled roads, all of the advance warning signs prescribed for
major construction might not be needed.
Option:
Utility work, maintenance, or minor construction can occur within the TTC zone limits of
a major construction project, and additional warning signs may be needed.
Guidance:
Utility, maintenance, and minor construction signing and TTC should be coordinated
with appropriate authorities so that road users are not confused or misled by the
additional TTC devices.
The ROAD (STREET) WORK (W20-1) sign (see Figure 7-4, Sheet 3 of 3), which serves
as a general warning of obstructions or restrictions, should be located in advance of the
work space or any detour, on the road where the work is taking place.
Where traffic can enter a TTC zone from a crossroad or a major (high-volume) driveway,
an advance warning sign should be used on the crossroad or major driveway.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
The ROAD (STREET) WORK (W20-1) sign shall have the legend ROAD
(STREET) WORK, XX BLOCKS, XX FEET, XX MILES, or AHEAD, as per the
functional classification of the road or as deemed necessary by the DDOT Engineer.
Guidance:
The DETOUR (W20-2) sign (see Figure 7-4 Sheet 3 of 3) should be used in advance of a
road user detour over a different roadway or route.
Standard:
The DETOUR sign shall have the legend DETOUR, XX BLOCKS, XX FEET, XX
MILES, or AHEAD, as per the functional classification of the road or as deemed
necessary by the DDOT Engineer.
Guidance:
The ROAD (STREET) CLOSED (W20-3) sign (see Figure 7-4, Sheet 3 of 3) should be
used in advance of the point where a highway is closed to all road users or to all but
local road users.
Standard:
The ROAD (STREET) CLOSED sign shall have the legend ROAD (STREET)
CLOSED, XX FEET, XX MILES, or AHEAD, as per the functional classification of
the road or as deemed necessary by the DDOT Engineer.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
The ONE LANE ROAD (W20-4) sign (see Figure 7-4, Sheet 3 of 3) shall be used
only in advance of that point where motor vehicle traffic in both directions must use
a common single lane. It shall have the legend ONE LANE ROAD, XX BLOCKS,
XX FEET, XX MILES, or AHEAD, as per the functional classification of the road
or as deemed necessary by the DDOT Engineer.
The LANE(S) CLOSED (W20-5, W20-5a) sign (see Figure 7-4, Sheet 3 of 3) shall be
used in advance of that point where one or more through lanes of a multi-lane
roadway are closed.
For a single lane closure, THE LANE CLOSED (W20-5) sign (see Figure 7-4, Sheet
3 of 3) shall have the legend RIGHT (LEFT) LANE CLOSED, XX BLOCKS, XX
FEET, XX MILES, or AHEAD. Where two adjacent lanes are closed, the W20-5a
sign (see Figure 7-4, Sheet 3 of 3) shall have the legend RIGHT (LEFT) TWO
LANES CLOSED, XX BLOCKS, XX FEET, XX MILES, or AHEAD, as per the
functional classification of the road or as deemed necessary by the DDOT Engineer.
Guidance:
The CENTER LANE CLOSED AHEAD (W9-3,W9-3a) sign (see Figure 7-4, Sheet 2 of 3)
should be used in advance of that point where work occupies the center lane(s) and
approaching motor vehicle traffic is directed to the right or left of the work zone in the
center lane.
Option:
The CENTER LANE CLOSED AHEAD (W9-3a) symbol sign (see Figure 6H-38 of the
MUTCD) may be substituted for the CENTER LANE CLOSED AHEAD (W9-3) word
message sign.
Guidance:
The THRU TRAFFIC MERGE LEFT (RIGHT) (W4-7) sign (see Figure 7-4, Sheet 1 of 3)
should be used in advance of an intersection where one or more lane closures on the far
side of a multi-lane intersection require through vehicular traffic on the approach to the
intersection to use the left (right) lane to proceed through the intersection.
Option:
The LANE ENDS (W4-2) symbol sign (see Figure 7-4, Sheet 1 of 3) may be used to
warn motorists of the reduction in the number of lanes for moving motor vehicle traffic in
the direction of travel on a multi-lane roadway.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
When work is being done on a ramp, but the ramp remains open, the ON RAMP (W13-4)
plaque (see Figure 7-4, Sheet 3 of 3) should be used to supplement the advance ROAD
WORK sign.
The RAMP NARROWS (W5-4) sign (see Figure 7-4, Sheet 1 of 3) should be used in
advance of the point where work on a ramp reduces the normal width of the ramp along
a part or all of the ramp.
Option:
The SLOW TRAFFIC AHEAD (W23-1) sign (see Figure 7-4, Sheet 3 of 3) may be used
on a shadow vehicle, usually mounted on the rear of the most upstream shadow vehicle,
along with other appropriate signs for mobile operations to warn of slow moving work
vehicles. A ROAD WORK (W20-1) sign may also be used with the SLOW TRAFFIC
AHEAD sign.
An EXIT OPEN (E5-2), EXIT CLOSED (E5-2a), or EXIT ONLY (E5-3) sign (see
Figure 7-5) may be used to supplement other warning signs where work is being
conducted in the vicinity of an exit ramp and where the exit maneuver for motor vehicle
traffic using the ramp is different from the normal condition.
Guidance:
When an exit ramp is closed, an EXIT CLOSED panel with a black legend and border on
an orange background should be placed diagonally across the interchange/intersection
guide signs.
The Flagger (W20-7a) symbol sign (see Figure 7-4, Sheet 3 of 3) should be used in
advance of any point where a flagger is stationed to control road users.
Option:
A distance legend may be displayed on a supplemental plaque below the Flagger sign.
The sign may be used with appropriate legends or in conjunction with other warning
signs, such as the BE PREPARED TO STOP (W3-4) sign (see Figure 7-4, Sheet 1 of 3).
The FLAGGER (W20-7) word message sign with distance legends may be substituted for
the Flagger (W20-7a) symbol sign.
Standard:
The Flagger sign shall be removed, covered, or turned away from road users when
the flagging operations are not occurring.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
When one roadway of a normally divided highway is closed, with two-way vehicular
traffic maintained on the other roadway, the TWO-WAY TRAFFIC (W6-3) sign (see
Figure 7-4, Sheet 1 of 3) should be used at the beginning of the two-way vehicular traffic
section and at intervals to remind road users of opposing vehicular traffic.
Option:
A Workers (W21-1a) symbol sign (see Figure 7-4, Sheet 3 of 3) may be used to alert road
users of workers in or near the roadway.
Guidance:
In the absence of other warning devices, a Workers symbol sign should be used when
workers are in the roadway.
Option:
The WORKERS (W21-1) word message sign may be used as an alternate to the Workers
(W21-1a) symbol sign.
Guidance:
The FRESH OIL (TAR) (W21-2) sign (see Figure 7-4, Sheet 3 of 3) should be used to
warn road users of the surface treatment.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
The ROAD MACHINERY AHEAD (W21-3) sign (see Figure 7-4, Sheet 3 of 3) may be
used to warn of machinery operating in or adjacent to the roadway.
Motorized Traffic (W8-6, W11-10) signs may be used to alert road users to locations
where unexpected travel on the roadway or entries into or departures from the roadway
by construction vehicles might occur. The TRUCK CROSSING (W8-6) word message
sign may be used as an alternate to the Truck Crossing symbol (W11-10) sign (see Figure
7-4, Sheet 2 of 3) where there is an established construction vehicle crossing of the
roadway.
Support:
These locations might be relatively confined or might occur randomly over a segment of
roadway.
Standard:
The Shoulder Work signs (W21-5, W21-5a, W21-5b) shall have the legend
SHOULDER WORK (W21-5), RIGHT (LEFT) SHOULDER CLOSED (W21-5a),
or RIGHT (LEFT) SHOULDER CLOSED XX FEET or AHEAD (W21-5b).
Support:
Shoulder Work signs (W21-5, W21-5a, W21-5b) (see Figure 7-4, Sheet 3 of 3) warn of
maintenance, reconstruction, or utility operations on the highway shoulder where the
roadway is unobstructed.
Option:
The Shoulder Work signs may be used in advance of the point on a non-limited access
highway where there is shoulder work. It may be used singly or in combination with a
ROAD WORK NEXT XX MILES or XX FEET OR XX BLOCKS or WORK AHEAD
sign, as per the functional classification of the road or as deemed necessary by the DDOT
Engineer
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
The SURVEY CREW (W21-6) sign (see Figure 7-4, Sheet 3 of 3) should be used to warn
of surveying crews working in or adjacent to the roadway.
Option:
The UTILITY WORK (W21-7) sign (see Figure 7-4, Sheet 4 of 3) may be used as an
alternate to the ROAD (STREET) WORK (W20-1) sign for utility operations on or
adjacent to a highway.
Standard:
The UTILITY WORK sign shall carry the legend UTILITY WORK, XX BLOCKS,
XX FEET, XX MILES, or AHEAD, as per the functional classification of the road
or as deemed necessary by the DDOT Engineer.
Option:
The SOFT SHOULDER (W8-4) sign (see Figure 7-4, Sheet 2 of 3) may be used to warn
of a soft shoulder condition.
The LOW SHOULDER (W8-9) sign (see Figure 7-4, Sheet 2 of 3) may be used to warn
of a shoulder condition where there is an elevation difference of less than three inches
(75 mm) between the shoulder and the travel lane.
Guidance:
The SHOULDER DROP OFF (W8-9a) sign (see Figure 7-4, Sheet 2 of 3) should be used
when an unprotected shoulder drop-off, adjacent to the travel lane, exceeds three inches
(75 mm) in depth for a continuous length along the roadway, based on engineering
judgment.
The UNEVEN LANES (W8-11) sign (see Figure 7-4, Sheet 2 of 3) should be used during
operations that create a difference in elevation between adjacent lanes that are open to
travel.
The NO CENTER STRIPE (W8-12) sign (see Figure 7-4, Sheet 3 of 3) should be used
when the work obliterates the centerline pavement markings. This sign should be placed
at the beginning of the TTC zone and repeated at XX feet intervals in long TTC zones.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
The DOUBLE REVERSE CURVE (W24-1, W24-1a, or W24-1b) sign (see Figure 7-4,
Sheet 3 of 3) may be used when the tangent distance between two reverse curves is less
than 600 feet (180 meters), thus making it difficult for a second Reverse Curve (W1-4
Series) sign to be placed between the curves.
Standard:
Option:
Advance warning signs may be used by themselves or with other advance warning signs.
Besides the warning signs specifically related to TTC zones, several other warning signs
in Part 2 may apply in TTC zones.
Standard:
Except as noted previously, other warning signs that are used in TTC zones shall
have black legends and borders on an orange background.
Option:
Guidance:
Special warning signs should conform to the general requirements of color, shape, and
alphabet size and series. The sign message should be brief, legible, and clear.
Option:
In combination with a warning sign, an Advisory Speed (W13-1) plaque (see Figure 7-4,
Sheet 2 of 3) may be used to indicate a recommended safe speed through the TTC zone.
Standard:
The Advisory Speed plaque shall not be used in conjunction with any sign other
than a warning sign, nor shall it be used alone. When used with orange Temporary
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Traffic Control (TTC) zone signs, this plaque shall have a black legend and border
on an orange background. The sign shall be at least 24 x 24 inches (600 x 600 mm) in
size when used with a sign that is 36 x 36 inches (900 x 900 mm) or larger. Except in
emergencies, an Advisory Speed plaque shall not be mounted until the
recommended speed is determined by the highway agency.
Option:
In combination with a warning sign, a Supplementary Distance (W7-3a) plaque with the
legend NEXT XX MILES or XX FEET, as deemed necessary by the DDOT Engineer,
may be used to indicate the length of highway over which a work activity is being
conducted or over which a condition exists in the TTC zone.
In long TTC zones, Supplementary Distance plaques with the legend NEXT XX MILES
or XX FEET, as per functional classification or as deemed necessary by the DDOT
Engineer, may be placed in combination with warning signs at regular intervals within
the zone to indicate the remaining length of highway over which the TTC work activity
or condition exists.
Standard:
Guidance:
When used in Temporary Traffic Control zones, the Supplementary Distance plaque with
the legend NEXT XX MILES or XX FEET, as per the functional classification of the road
or as deemed necessary by the DDOT Engineer, should be placed below the initial
warning sign designating that, within the approaching zone, a temporary work activity or
condition exists.
Support:
Guide signs along highways provide road users with information to help them along their
way through the TTC zone. The design of guide signs is presented in Part 2 of the
MUTCD.
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
If additional temporary guide signs are used in TTC zones, they shall have a black
legend and border on an orange background.
Option:
Guide signs used in TTC incident management situations may have a black legend and
border on a fluorescent pink background.
When directional signs and street name signs are used in conjunction with detour routing,
these signs may have a black legend and border on an orange background.
When permanent directional signs or permanent street name signs are used in conjunction
with detour signing, they may have a white legend on a green background.
Guidance:
The ROAD WORK NEXT XX MILES (G20-1) sign (see Figure 7-4, Sheet 3 of 3) should
be installed in advance of TTC zones that are more than two miles in length.
Option:
The ROAD WORK NEXT XX MILES sign may be mounted on a Type III barricade.
The sign may also be used for TTC zones of shorter length.
Standard:
The distance shown on the ROAD WORK NEXT XX MILES sign shall be stated to
the nearest whole mile.
Guidance:
When used, the END ROAD WORK (G20-2) sign (see Figure 7-4, Sheet 3 of 3) should be
placed near the end of the termination area, as determined by engineering judgment.
Option:
The END ROAD WORK sign may be installed on the back of a warning sign facing the
opposite direction of road users or on the back of a Type III barricade.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Each detour shall be adequately marked with standard temporary route signs and
destination signs.
Option:
Detour signs in TTC incident management situations may have a black legend and border
on a fluorescent pink background.
The Detour Arrow (M4-10) sign (see Figure 7-5) may be used where a detour route has
been established.
The DETOUR (M4-8) sign (see Figure 7-5) may be mounted at the top of a route sign
assembly to mark a temporary route that detours from a highway, bypasses a section
closed by a TTC zone, and rejoins the highway beyond the TTC zone.
Guidance:
The Detour Arrow (M4-10) sign should normally be mounted just below the ROAD
CLOSED (R11-2, R11-3a, or R11-4) sign. The Detour Arrow sign should include a
horizontal arrow pointed to the right or left as required.
The DETOUR (M4-9) sign (see Figure 7-5) should be used for unnumbered highways, for
emergency situations, for periods of short durations, or where, over relatively short
distances, road users are guided along the detour and back to the desired highway
without route signs.
A Street Name sign should be placed above, or the street name should be incorporated
into, a DETOUR (M4-9) sign to indicate the name of the street being detoured.
Option:
The END DETOUR (M4-8a) or END (M4-8b) sign (see Figure 7-5) may be used to
indicate that the detour has ended.
Guidance:
When the END DETOUR sign is used on a numbered highway, the sign should be
mounted above a sign after the end of the detour.
The Pedestrian/Bicycle Detour (M4-9a) sign (see Figure 7-5) should be used where a
pedestrian/bicycle detour route has been established because of the closing of a
pedestrian/bicycle facility to through traffic.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
If used, the Pedestrian/Bicycle Detour sign shall have an arrow pointing in the
appropriate direction.
Option:
The Pedestrian Detour (M4-9b) sign or Bicycle Detour (M4-9c) sign (see Figure 7-5)
may be used where a pedestrian or bicycle detour route (not both) has been established
because of the closing of the pedestrian or bicycle facility to through traffic.
Standard:
Standard:
Support:
Portable Changeable Message signs are used most frequently on high-density urban
freeways, but have applications on all types of highways where highway alignment, road
user routing problems, or other pertinent conditions require advance warning and
information.
Guidance:
The components of a Portable Changeable Message sign should include a message sign
panel, control systems, a power source, and mounting and transporting equipment.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Portable Changeable Message signs should subscribe to the principles established in this
Manual and, to the extent practical, with the design (color, letter size and shape, and
borders) and applications prescribed in this Manual, except that the reverse colors for
the letters and the background are considered acceptable.
The front face of the sign should be covered with a protective material. The color of the
elements should be yellow or orange on a black background.
Portable Changeable Message signs should be visible from 0.5 miles under both day and
night conditions. For a trailer or large truck mounted sign, the letter height should be a
minimum of 18 inches. For Portable Changeable Message signs mounted on the back of
service patrol trucks or work trucks, the letter height should be a minimum of 10 inches.
The message should be legible from a minimum distance of 650 feet for Portable
Changeable Message signs mounted on a trailer or large truck and 330 feet for Portable
Changeable Message signs mounted on service patrol or work trucks.
The message panel should have adjustable display rates, so that the entire message can
be read at least twice at the posted speed, the off-peak 85th-percentile speed prior to
work starting, or the anticipated operating speed.
Option:
Standard:
The control system shall include a display screen upon which messages can be
reviewed before being displayed on the message sign. The control system shall be
capable of maintaining memory when power is unavailable.
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Portable Changeable Message signs shall be equipped with a power source and a
battery back-up to provide continuous operation when failure of the primary power
source occurs.
The mounting of Portable Changeable Message signs shall be such that the bottom
of the message sign panel shall be a minimum of seven feet above the roadway when
it is in the operating mode.
The text of the messages shall not scroll or travel horizontally or vertically across
the face of the sign.
Support:
Guidance:
Support:
The primary purpose of Portable Changeable Message signs in temporary traffic control
zones is to advise the road user of unexpected situations. Some typical applications
include the following:
Guidance:
When Portable Changeable Message signs (PCMS) are used for route diversion, they
should be placed far enough in advance of the diversion to allow road users ample
opportunity to exit the affected highway. The PCMS should be sited and aligned to ensure
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
legibility. Multiple PCMSs should be placed on the same side of the roadway, separated
from each other a minimum distance of 1,000 feet.
Portable Changeable Message signs should be placed on the shoulder of the roadway or,
if practical, further from the traveled lane. They should be delineated with retroreflective
temporary traffic control devices or when within the clear zone, shielded with a barrier
or crash cushion. When Portable Changeable Message signs are not being used, they
should be removed or placed out of the clear zone; if not removed, they should be
shielded; or if the previous two options are not feasible, they should be delineated with
retroreflective temporary traffic control devices.
Standard:
When used in unmanned work zones, Group 2 channelizing devices shall be used to
delineate Portable Changeable Message signs.
Standard:
An arrow panel shall be a sign with a matrix of elements capable of either flashing
or sequential displays. This sign shall provide additional warning and directional
information to assist in merging and controlling road users through or around a
temporary traffic control zone.
Guidance:
An arrow panel should be placed on the shoulder of the roadway or, if practical, further
from the traveled lane. It should be delineated with retroreflective temporary traffic
control devices, or when within the clear zone, shielded with a barrier or crash cushion.
When an arrow panel is not being used, it should be removed; if not removed, it should
be shielded; or if the previous two options are not feasible, it should be delineated with
retroreflective temporary traffic control devices.
Standard:
When used in unmanned work zones, Group 2 channelizing devices shall be used to
delineate arrow panels.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Arrow panels shall meet the minimum size, legibility distance, number of elements,
and other specifications shown on Figure 7-6 and Table 7-1.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Flashing Arrow
Sequential Arrow
Sequential Chevron
Flashing Caution
Support:
Type A arrow panels are appropriate for use on low-speed (below 35 mph) urban streets.
Type B arrow panels are appropriate for intermediate-speed (35 mph to 44 mph) facilities
and for maintenance or mobile operations on high-speed (45 mph and greater) roadways.
Type C arrow panels are intended to be used on high-speed, high-volume motor vehicle
traffic control projects.
Standard:
All arrow panels shall be finished in nonreflective black. The arrow panel shall be
mounted on a vehicle, a trailer, or other suitable support.
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Arrow Panels
Minimum
Type Minimum Size
Lamps
A 24’ x 48’ 12
B 30’ x 60’ 13
C 48’ x 96’ 15
Guidance:
The minimum mounting height of an arrow panel should be seven feet from the roadway
to the bottom of the panel, except on vehicle-mounted panels, which should be as high as
practical.
Standard:
Arrow panel elements shall be capable of at least 50 percent dimming from full
brilliance. The dimmed mode shall be used for nighttime operation of arrow panels.
Guidance:
Standard:
The arrow panel shall have suitable elements capable of the various operating
modes. The color presented by the elements shall be yellow.
Guidance:
If an arrow panel consisting of a bulb matrix is used, the elements should be recess-
mounted or equipped with an upper hood of not less than 180 degrees.
Standard:
The minimum element on-time shall be 50 percent for the flashing mode, with equal
intervals of 25 percent for each sequential phase. The flashing rate shall be not less
than 25, nor more than 40, flashes per minute.
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An arrow panel in the arrow or chevron mode shall be used only for stationary or
moving lane closures on multi-lane roadways.
For shoulder work blocking the shoulder, for roadside work near the shoulder, or
for temporarily closing one lane on a two-lane, two-way roadway, an arrow panel
shall be used only in the caution mode.
Guidance:
For a stationary lane closure, the arrow panel should be located on the shoulder at the
beginning of the merging taper. Where the shoulder is narrow, the arrow panel should be
located in the closed lane.
Standard:
When arrow panels are used to close multiple lanes, a separate arrow panel shall be
used for each closed lane.
Guidance:
When arrow panels are used to close multiple lanes, if the first arrow panel is placed on
the shoulder, the second arrow panel should be placed in the first closed lane at the
beginning of the second merging taper. When the first arrow panel is placed in the first
closed lane, the second arrow panel should be placed in the second closed lane at the
downstream end of the second merging taper.
For mobile operations where a lane is closed, the arrow panel should be located to
provide adequate separation from the work operation to allow for appropriate reaction
by approaching motorists.
Standard:
Option:
A portable changeable message sign may be used to simulate an arrow panel display.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
A high-level warning device (flag tree) may supplement other temporary traffic control
devices in temporary traffic control zones.
Support:
A high-level warning device is designed to be seen over the top of typical passenger cars.
Standard:
A high-level warning device shall consist of a minimum of two flags with or without
a Type B high-intensity flashing warning light. The distance from the roadway to
the bottom of the lens of the light and to the lowest point of the flag material shall be
not less than eight feet. The flag shall be 16 inches square or larger and shall be
orange or fluorescent red-orange in color.
Option:
Support:
High-level warning devices are most commonly used in high-density road user situations
to warn road users of short-term operations.
Standard:
Support:
The function of channelizing devices is to warn road users of conditions created by work
activities in or near the roadway and to guide road users. Channelizing devices include
cones, tubular markers, vertical panels, plastic drums, barricades, and temporary raised
islands.
Channelizing devices provide for smooth and gradual motor vehicle traffic flow from one
lane to another, onto a bypass or detour, or into a narrower traveled way. They are also
used to separate motor vehicle traffic from the work space, pavement drop-offs,
pedestrian or bicycle paths, or opposing directions of motor vehicle traffic.
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Fragments or other debris from the device or the ballast should not pose a significant
hazard to road users or workers in the immediate area.
The spacing of channelizing devices should be as shown in Table 7-2. The spacing of
channelizing devices in tangent sections of the work zone is normally twice the distance
for devices used in the taper and around curves of six degrees and greater.
When channelizing devices have the potential of leading motor vehicle traffic out of the
intended motor vehicle traffic space, the channelizing devices should be extended a
distance in feet of two times the speed limit in mph beyond the end of the transition area.
Channelizing devices are elements in a total system of traffic control devices for use in
temporary traffic control zones. These elements shall be preceded by a subsystem of
warning devices that are adequate in size, number, and placement for the type of highway
on which the work is to take place. Standard designs of channelizing devices are shown
in Figure 7-7.
Option:
Warning lights may be added to channelizing devices in areas with frequent fog, snow, or
severe roadway curvature, or where visual distractions are present.
Standard:
Warning lights shall flash when placed on channelizing devices used alone or in a
cluster to warn of a condition. Warning lights placed on channelizing devices used
in a series to channelize road users shall be steady-burn. Barrier vertical panels
shall not be installed on Group 1 or 2 channelizing devices.
Option:
The name and telephone number of the highway agency, contractor, or supplier may be
shown on the non-retroreflective surface of all types of channelizing devices.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
The letters and numbers of the name and telephone number shall be non-
retroreflective and not over two inches in height.
Guidance:
Particular attention should be given to maintaining the channelizing devices to keep them
clean, visible, and properly positioned at all times.
Standard:
Devices that are damaged or have lost a significant amount of their retroreflectivity
and effectiveness shall be replaced. Replacement and correction of ineffective
channelizing devices shall be accomplished in accordance with the American Traffic
Safety Service Association (ATSSA)'s Quality Standards for Work Zone Traffic
Control Devicesv.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
7.14.1 CONES
Standard:
Cones shall be predominantly orange and shall be made of a material that can be
struck without causing damage to the impacting vehicle. The height of cones for use
on all roadways shall be 36 inches.
Option:
When workers are present to maintain them, traffic cones may be used to channelize road
users, divide opposing motor vehicle traffic lanes, divide lanes when two or more lanes
are kept open in the same direction, and delineate short duration maintenance and utility
work.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
Steps should be taken to ensure that cones will not be blown over or displaced by wind or
moving motor vehicle traffic.
Option:
Support:
Some cones are constructed with bases that can be filled with ballast. Others have
specially weighted bases or weight such as sandbag rings that can be dropped over the
cones and onto the base to provide added stability.
Guidance:
Standard:
When workers are not present on the jobsite to maintain the cones, Group 2
channelizing devices shall be used for channelization.
Standard:
Tubular markers (see Figure 7-7) shall be predominantly orange and shall be not
less than 36 inches high and two inches wide facing road users. They shall be made
of a material that can be struck without causing damage to the impacting vehicle.
Guidance:
Tubular markers have less visible area than other devices and should be used only where
space restrictions do not allow for the use of other more visible devices.
Tubular markers should be stabilized by affixing them to the pavement, by using weighted
bases, or weights such as sandbag rings that can be dropped over the tubular markers
and onto the base to provide added stability. Ballast should be kept to the minimum
amount needed.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Tubular markers may be used effectively to divide opposing lanes of road users, divide
motor vehicle traffic lanes when two or more lanes are kept open in the same direction,
and to delineate the edge of a pavement drop off where space limitations do not allow the
use of larger devices.
Standard:
A tubular marker shall be attached to the pavement to display the minimum 2-inch
width to the approaching road users.
Standard:
Vertical panels shall be eight to 12 inches in width and at least 36 inches in height.
They shall have orange and white diagonal stripes and be retroreflectorized.
Vertical panels shall be mounted with the top a minimum of 36 inches above the
roadway, and a minimum of 42 inches above the pedestrian travel way. Vertical
panels shall be mounted with the bottom no greater than 12 inch above the ground.
Where the height of the vertical panel itself is 36 inches or greater, a panel stripe
width of six inches shall be used. Markings for vertical panels shall be alternating
orange and white retroreflective stripes, sloping downward at an angle of 45 degrees
in the direction the motor vehicle traffic is to pass. Vertical panels used on
expressways, freeways, and other high-speed roadways shall have a minimum of 270
square inches retroreflective area facing motor vehicle traffic.
Option:
Where space is limited, vertical panels may be used to channelize motor vehicle traffic,
divide opposing lanes, or replace barricades when approved by the DDOT Engineer.
7.14.4 DRUMS
Standard:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
have a minimum of two orange and two white stripes with the top stripe being
orange. Any nonretroreflectorized spaces between the horizontal orange and white
stripes, shall not exceed three inches wide. Drums shall have closed tops that will not
allow collection of construction debris or other debris.
Support:
Drums are highly visible, have good target value, give the appearance of being
formidable obstacles and, therefore, command the respect of road users. They are
portable enough to be shifted from place to place within a temporary traffic control zone
in order to accommodate changing conditions but are generally used in situations where
they will remain in place for a prolonged period of time.
Option:
Although drums are most commonly used to channelize or delineate road user flow, they
may also be used alone or in groups to mark specific locations.
Guidance:
Drums should not be weighted with sand, water, or any material to the extent that would
make them hazardous to road users or workers when struck. Drums used in regions
susceptible to freezing should have drain holes in the bottom so that water will not
accumulate and freeze causing a hazard if struck by a road user.
Standard:
Drums shall be used in all unmanned work zone locations and in all lane closure
tapers on limited access highways for nighttime operations.
Support:
A barricade is a portable or fixed device having three rails with appropriate markings and
is used to control road users by closing or restricting all or a portion of the right-of-way.
Standard:
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The minimum length for Type III Barricades shall be 48 inches. Each barricade rail
shall be eight to 12 inches wide. Barricades used on expressways, freeways and other
high-speed roadways shall have a minimum of 270 square-inches of retroreflective
area facing road users.
Guidance:
Where barricades extend entirely across a roadway, the stripes should slope downward
in the direction toward which road users must turn.
Where both right and left turns are provided, the barricade stripes should slope
downward in both directions from the center of the barricade or barricades (inverted V-
shape).
Where no turns are intended, the stripes should be positioned to slope downward toward
the center of the barricade or barricades (V-shape).
Barricade rails should be supported in a manner that will allow them to be seen by the
road user and in a manner that provides a stable support that is not easily blown over or
displaced.
Standard:
Guidance:
Option:
Sandbags may be placed on the lower parts of the frame or the stays of barricades to
provide the required ballast.
Standard:
Ballast shall not be placed on top of any striped rail. Barricades shall not be
ballasted by non-deformable objects such as rocks or chunks of concrete.
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Type III Barricades used at a road closure may be placed completely across a roadway or
from curb to curb.
Standard:
Where a provision is made for access of authorized equipment and vehicles, the
responsibility for Type III Barricades shall be assigned to a person to ensure proper
closure at the end of each work day.
Support:
When a highway is legally closed but access must still be allowed for local road users,
barricades usually are not extended completely across the roadway.
Standard:
A sign (see earlier discussion in previous section) shall be installed with the
appropriate legend concerning permissible use by local road users. Adequate
visibility of the barricades from both directions shall be provided.
Option:
Standard:
Support:
Temporary traffic barriers are not temporary traffic control devices in themselves;
however, when placed in a position identical to a line of channelizing devices and marked
and/or equipped with appropriate channelization features to provide guidance and
warning both day and night, they serve as temporary traffic control devices.
Standard:
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Temporary traffic barriers shall not be used solely to channelize road users, but also
to protect the work space (see Section 6F.77 of the MUTCD). For nighttime use, the
temporary traffic barrier shall be supplemented with delineation.
Guidance:
Temporary traffic barriers should not be used for a merging taper except in low-speed
urban areas. Temporary traffic barriers should not be used for a constricted/restricted
temporary traffic control zone.
When it is necessary to use a temporary traffic barrier for a merging taper in low-speed
urban areas or for a constricted/restricted temporary traffic control zone, the taper shall
be delineated and the taper length should be designed to optimize road user operations
considering the available geometric conditions
When used for channelization, temporary traffic barriers should be of a light color for
increased visibility.
Standard:
Channelizing devices other than those described in this Manual shall require
approval from DDOT Engineer or a review and/or engineering study prior to their
use.
Guidance:
Other channelizing devices should conform to the general size, color, stripe pattern,
retroreflection, and placement characteristics established for the devices described in
this Manual.
Standard:
Temporary raised islands shall be used only in combination with pavement striping
and other suitable channelizing devices.
Option:
A temporary raised island may be used to separate motor vehicle traffic flows in two-
lane, two-way operations on roadways having a motor vehicle traffic volume range of
4,000 to 15,000 average daily traffic (ADT) and on freeways having a motor vehicle
traffic volume range of 22,000 ADT to 60,000 ADT.
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Temporary raised islands also may be used in other than two-lane, two-way operations
where physical separation of motor vehicle traffic from the temporary traffic control zone
is not required.
Guidance:
Temporary raised islands should have the basic dimensions of four inches in height by 15
to 18 inches in width and have rounded or chamfered corners.
The temporary raised islands should not be designed in such a manner that they would
cause a motorist to lose control of the vehicle if the vehicle inadvertently strikes the
temporary raised island. If struck, pieces of the island should not be dislodged to the
extent that they could penetrate the occupant compartment or involve other vehicles.
Orange flexible post delineators 36 inches in height and 2.25 to four inches in width
should be placed on top of the raised island for delineation.
Standard:
Flexible post delineators shall be spaced every 80 feet, with a temporary pavement
marker spaced in between each delineator on top of the temporary raised median.
Retro-reflective sheeting shall be placed three inches from the top of each flexible
post delineator.
Standard:
The provisions of this Section shall not be considered applicable for short-term,
mobile, or incident management temporary traffic control zones.
Pavement markings shall be maintained along paved streets and highways in all
long- and intermediate-term stationary temporary traffic control zones. All
pavement markings shall be in accordance with Chapters 3A and 3B of the
MUTCD, except as indicated in previous sections of this manual. Pavement
markings shall match the markings in place at both ends of the temporary traffic
control zone. Pavement markings shall be placed along the entire length of any
surfaced detour or temporary roadway prior to the detour or roadway being opened
to road users.
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Pavement marking obliteration shall leave a minimum of pavement scars and shall
remove old marking material. Painting over existing pavement markings with black
paint or spraying with asphalt shall not be accepted as a substitute for removal or
obliteration.
Guidance:
Road users should be provided pavement markings within a temporary traffic control
zone comparable to the pavement markings normally maintained along such roadways,
particularly at either end of the temporary traffic control zone.
The intended vehicle path should be defined in day, night, and twilight periods under
both wet and dry pavement conditions.
The work should be planned and staged to provide for the placement and removal of the
pavement markings. Markings should be provided in intermediate-term, stationary work
zones.
Option:
Support:
Temporary pavement markings are those that are allowed to remain in place until the
earliest date when it is practical and possible to install pavement markings that meet the
MUTCD Part 3 standards for pavement markings.
Guidance:
Temporary pavement markings should not be in place for more than two weeks unless
justified by an engineering study.
Standard:
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Option:
Half-cycle lengths with a minimum of 2-foot stripes may be used on roadways with
severe curvature (see Section 3A.06 of the MUTCD). This applies to centerlines in
passing zones and lane lines.
For temporary situations of three calendar days or less, for a 2- or 3-lane road, no-passing
zones may be identified by using “NO PASSING ZONE” (W14-3) signs rather than
pavement markings. Also, “NO PASSING ZONE” signs may be used instead of
pavement markings on low-volume roads (as defined in Section 5A.01 of the MUTCD)
for longer periods in accordance with the District’s policy.
Guidance:
The NO PASSING ZONE signs should be placed in accordance with Sections 2B.24,
2B.25, and 2C.32 of the MUTCD.
The temporary use of edge lines, channelizing lines, lane reduction transitions, gore
markings, and other longitudinal markings, and the various non-longitudinal markings
(such as stop lines, railroad crossings, crosswalks, words or symbols) should be in
accordance with the District’s policy.
Standard:
7.14.8.5 DELINEATORS
Standard:
When used, delineators shall combine with or supplement other temporary traffic
control devices. They shall be mounted on crashworthy supports so that the
reflecting unit is approximately four feet above the near roadway edge. The
standard color for delineators used along both sides of two-way streets and
highways and the right side of one-way roadways shall be white. Delineators used
along the left side of one way roadways shall be yellow.
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Guidance:
Spacing along roadway curves should be as set forth in the MUTCD and should be such
that several delineators are always visible to the motorist.
Option:
Delineators may be used in temporary traffic control zones to indicate the alignment of
the roadway and to outline the required vehicle path through the temporary traffic control
zone.
Guidance:
Support:
Four types of lighting devices are commonly used in temporary traffic control zones.
They are floodlights, flashing warning beacons, warning lights, and steady-burn electric
lamps.
Option:
Support:
Standard:
7.15.1 FLOODLIGHTS
Support:
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Guidance:
When nighttime work is being performed, floodlights should be used to illuminate the
work area, flagger stations, equipment crossings, and other areas.
Standard:
Floodlighting shall not produce a disabling glare condition for approaching road
users.
The adequacy of the floodlight placement and elimination of potential glare shall be
determined by driving through and observing the floodlighted area from each
direction on all approaching roadways after the initial floodlight setup, at night, and
periodically during each shift.
Support:
Research indicates that five feet candles are a desirable nighttime illumination level
where workers are active.
Support:
Flashing warning beacons are often used to supplement a temporary control device.
Standard:
Flashing warning beacons shall comply with the provisions of Chapter 4K of the
MUTCD. A flashing warning beacon shall be a flashing yellow light with a
minimum nominal diameter of eight inches.
Guidance:
Support:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
Type A, Type B, Type C, and Type D 360-degree warning lights are portable,
powered, yellow, lens-directed, enclosed lights.
Warning lights shall be in accordance with the current ITE "Purchase Specification
for Flashing and Steady-Burn Warning Lights.”
When warning lights are used, they shall be mounted on signs or channelizing
devices in a manner that, if hit by an errant vehicle, they will not be likely to
penetrate the windshield.
Guidance:
The maximum spacing for warning lights should be identical to the channelizing device
spacing requirements.
Support:
The lightweight and portability of warning lights are advantages that make these devices
useful as supplements to the retroreflectorization on signs and channelizing devices. The
flashing lights are effective in attracting road users' attention.
Option:
Standard:
Flashing warning lights shall not be used for delineation, as a series of flashers fails
to identify the desired vehicle path.
Warning lights shall have a minimum mounting height of 30 inches to the bottom of
the lens.
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Support:
Type A Low-Intensity Flashing warning lights are used to warn road users during
nighttime hours that they are approaching or proceeding in a potentially hazardous area.
Option:
Support:
Type B High-Intensity Flashing warning lights are used to warn road users during both
daylight and nighttime hours that they are approaching a potentially hazardous area.
Option:
Type B warning lights are designed to operate 24 hours per day and may be mounted on
advance warning signs or on independent supports. Type C Steady-Burn warning lights
may be used during nighttime hours to delineate the edge of the traveled way.
Guidance:
When used to delineate a curve, Type C and Type D 360-degree Steady-Burn warning
lights should only be used on devices on the outside of the curve, and not on the inside of
the curve.
Support:
Steady-Burn electric lamps are a series of low-wattage, yellow, electric lamps, generally
hard-wired to a 110-volt external power source.
Option:
Steady-Burn electric lamps may be used in place of Type C Steady-Burn warning lights.
Guidance:
Standard:
Vehicle warning lights shall be either a rotating amber light or a high intensity
amber strobe light and meet the following conditions:
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Guidance:
During night operations, vehicles entering and exiting the work area should be equipped
with and have operating at least one rotating amber light or high intensity amber strobe
light.
Standard:
Temporary traffic control signals used to control road user movements through
temporary traffic control zones and in other temporary traffic control situations
shall meet the applicable provisions of Part 4 of the MUTCD.
Support:
Temporary traffic control signals are typically used in work zones such as temporary haul
road crossings; temporary one-way operations along a one-lane, two-way highway;
temporary one-way operations on bridges, reversible lanes, and intersections.
Standard:
One-lane, two-way motor vehicle traffic flow (see Chapter 4G of the MUTCD)
requires all-red interval of sufficient duration for road users to clear the portion of
the temporary traffic control zone controlled by the traffic control signals.
Safeguards shall be incorporated to avoid the possibility of conflicting signal
indications at each end of the temporary traffic control zone. All equipment shall be
in compliance with the current national standard and in excellent working
condition.
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Guidance:
When temporary traffic control signals are used, conflict monitors typical of traditional
traffic control signal operations should be used.
Standard:
The DDOT Engineer shall determine which traffic control signal will be used –
portable or temporarily mounted on fixed supports.
Option:
Guidance:
Temporary traffic control signals should only be used in situations where temporary
traffic control signals are preferable to other means of traffic control, such as changing
the work staging or work zone size to eliminate one-way motor vehicle traffic movements,
using flaggers to control one-way or crossing movements, using STOP or YIELD signs,
and using warning devices alone.
Support:
Temporary traffic barriers are devices designed to help prevent penetration by vehicles
while minimizing injuries to vehicle occupants and designed to protect workers,
bicyclists, and pedestrians.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Guidance:
Because the protective requirements of a temporary traffic control situation have priority
in determining the need for temporary traffic barriers, their use should be based on an
engineering study. When serving the additional function of channelizing motor vehicle
traffic, temporary traffic barriers should be a light color for increased visibility.
Standard:
Barrier vertical panels eight inches in width and 12 inches in height shall be
installed on top of the barrier. Panels shall be installed on 48-foot centers in the
transition or taper sections and on 96-foot centers in the tangent sections. A Type A
flashing light shall be installed on the barrier at the breakpoint where the transition
or taper ends and the barrier becomes parallel to the roadway. Barrier vertical
panels shall have a fluorescent orange retroreflective surface in the direction of
oncoming traffic.
The effect of striking the ends of barriers shall be mitigated by use of impact
attenuators or by flaring the ends of barriers away from the traveled way. Following
in the order of preference are the methods to be used in mitigating the effect of
striking the ends of barriers:
A. Where a guardrail exists, the guardrail shall be attached to the barrier with
the appropriate fixed object attachment.
B. Where a cut slope exists, the barrier shall be buried into the cut slope.
Drainage shall be provided as needed.
C. Extend end of barrier until it is beyond the established Clear Zone.
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D. When the barrier end is inside the desired Clear Zone, attenuator service
Type I or Type II (Sand Barrels) shall be used. Refer to Special Design
Drawings for type and quantity needed for each location.
Support:
A movable barrier is a linear system of connected barrier segments that can rapidly be
shifted laterally by using a specially designed transfer vehicle. The transfer is
accomplished in a manner that does not interfere with motor vehicle traffic in adjacent
lanes. Applications of movable barriers include the following:
1. Closing an additional lane during work periods while maintaining the advantage
of having the travel way separated from the work space by a barrier
2. Closing an additional lane during off-peak periods to provide extra space for
work activities without adversely impacting motor vehicle traffic flow
3. Creating a temporary reversible lane, thus providing unbalanced capacity
favoring the major direction of motor vehicle traffic flow
More specific information on the use of temporary traffic barriers is contained in
Chapters 8 and 9 of the AASHTO Roadside Design Guide.
Support:
Crash cushions are systems that mitigate the effects of errant vehicles that strike
obstacles, either by smoothly decelerating the vehicle to a stop when hit head-on or by
redirecting the errant vehicle. The two types of crash cushions that are used in temporary
traffic control zones are stationary crash cushions and truck-mounted attenuators. Crash
cushions in temporary traffic control zones help protect the motorist from the exposed
ends of barriers, fixed objects, shadow vehicles, and other obstacles. Specific information
on the use of crash cushions can be found in the AASHTO Roadside Design Guide.
Standard:
Crash cushions shall be periodically inspected to verify that they have not been hit
or damaged. Damaged crash cushions shall be promptly repaired or replaced to
maintain their crashworthiness.
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Support:
Stationary crash cushions are used in the same manner as permanent highway
installations to protect motorists from the exposed ends of barriers, fixed objects, and
other obstacles.
Standard:
Stationary crash cushions shall be designed for the specific application intended.
Support:
Trucks are often used as shadow vehicles to protect workers or work equipment from
errant vehicles.
These shadow vehicles are normally equipped with flashing arrows, changeable message
signs, and/or rotating/strobe lights located properly in advance of the workers and/or
equipment that they are protecting. However, these shadow vehicles might themselves
cause injuries to occupants of the errant vehicles if they are not equipped with truck-
mounted attenuators. The most effective placement of the shadow vehicle is in advance
of the first work crew, equipment, or hazard the traveling motorist would encounter.
Standard:
A. When closing a lane on a four or more lane roadway with a posted speed of
40 mph or greater
B. On ramps and loops of interstate and limited access highways
C. When a mobile operation occupies all or part of the travel lane on a multi-
lane roadway with a posted speed of 40 mph or greater
D. Other locations where Traffic Services Administration feels such protection
is warranted
TMA units used on all Limited Access highways, as well as on all four or more lane
primary roadways with posted speeds of 45 mph or greater, shall be NCHRP 350,
Test Level 3 units. On July 1, 2005, all TMA units shall conform to the requirements
of NCHRP 350, Test Level 3 regardless of where the units will be used.
The shadow truck with a TMA shall be positioned a sufficient distance (50 to 100
feet) in advance of the workers or equipment being protected to allow for
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appropriate vehicle roll-ahead but not so far that errant vehicles will travel around
the vehicle and strike the protected workers and/or equipment.
When all work crews, equipment, or hazards have been sufficiently removed from
the lane closure, the shadow truck shall be removed.
Support:
Shadow trucks should be used when installing and removing lane closures from the
roadway. In mobile operations, the shadow truck with a truck-mounted attenuator should
be 1,000 feet ҏin advance of the work vehicle.
Option:
Shadow trucks with TMA may be eliminated when their use would destroy or damage
uncured asphalt.
For additional operations or hazards located further downstream from the taper, a shadow
vehicle without a truck-mounted attenuator may be used for protection, placed a
sufficient distance (50 to 100 feet) in advance of the hazard.
Support:
Asphalt pavement resurfacing operations are typically those instances where shadow
trucks with TMA would destroy or damage uncured asphalt. Other operations being
accomplished under the same project would still require the use of TMA if their use
would not destroy or damage the uncured asphalt.
Examples of those operations include shoulder work where the adjacent lane is required
to be closed, pavement marking applications (except pavement marking tape being inlaid
into the new asphalt surface), and other similar type operations.
Standard:
During operation as a shadow vehicle with a TMA, the truck shall not be used as a
work operations vehicle. All material and/or equipment on the shadow vehicle TMA
shall be properly secured to prevent spillage if struck by an errant vehicle.
Guidance:
The attenuator should be in the full down-and-locked position when in use. For
stationary operations, the truck’s parking brake should be set and the front wheels
positioned straight ahead.
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Support:
Standard:
Support:
Vehicle-arresting systems are designed to prevent penetration into activity areas while
providing for smooth, safe deceleration for the errant vehicles. They can consist of
portable netting, cables, and energy-absorbing anchors.
Guidance:
Support:
Option:
Intervals between transverse rumble strips may be reduced as the distance to the
approached conditions is diminished in order to convey an impression that a closure
speed is too fast and/or that an action is imminent. A sign warning motorists of the onset
of rumble strips may be placed in advance of any rumble strip installation.
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Guidance:
Transverse rumble strips should be placed transverse to vehicular traffic movement. They
should not adversely affect overall pavement skid resistance under wet or dry conditions.
In urban commercial areas, even though a closer spacing might be warranted, transverse
rumble strips should be designed in a manner that does not promote panic braking or
erratic steering maneuvers by road users.
Transverse rumble strips should not be placed on sharp horizontal or vertical curves.
Rumble strips should not be placed through pedestrian crossings or bicycle routes.
7.21 SCREENS
Support:
Screens are used to block the road users’ view of activities that can be distracting.
Screens might improve safety and motor vehicle traffic flow where volumes approach the
roadway capacity because they discourage gawking and reduce headlight glare from
oncoming motor vehicle traffic.
Guidance:
Screens should not be mounted where they could adversely restrict motorist visibility and
sight distance and adversely affect the safe operation of vehicles.
Screens should be mounted on the top of temporary traffic barriers that separate two-way
motor vehicle traffic, especially in crossover areas.
Support:
The District of Columbia, as well as other States, FHWA, AASHTO, the Transportation
Research Board, and other organizations conduct research and experimentation on new
traffic control and safety devices. Users of this Manual are encouraged to stay abreast of
these current efforts and to use such devices with care so as to avoid presenting road
users with unusual or confusing situations that might be abnormal or unexpected.
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Standard:
New traffic control devices shall conform to the provisions for design, use, and
application set forth in this Manual. New traffic control devices that do not conform
to the provisions in this Manual shall be subject to experimentation, documentation,
and adoption following the provisions of Section 1A.10 of the MUTCD.
Approval shall be obtained from the Associate Director of TSA in the District
Department of Transportation for new traffic control devices prior to their use
and/or implementation.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
Each temporary traffic control zone is different. Many variables, such as location of
work, road type, geometrics, vertical and horizontal alignment, intersections,
interchanges, road user volumes, road vehicle mix (buses, trucks, and cars), and road user
speeds affect the needs of each zone. The goal of temporary traffic control in work zones
is safety with minimum disruption to road users. The key factor in promoting temporary
traffic control zone safety is proper judgment.
Guidance:
Typical traffic control figures should be altered, when necessary, to fit the conditions of a
particular temporary traffic control zone. The alteration should be documented.
Option:
Other devices may be added to supplement the devices shown in the typical traffic
control figures, while others may be deleted. The sign spacing and taper lengths may be
increased to provide additional time or space for motorist response.
Support:
Decisions regarding the selection of the most appropriate typical traffic control figure to
use as a guide for a specific temporary traffic control zone require an understanding of
each situation. Although there are many ways of categorizing work zone applications, the
four factors mentioned earlier (work duration, work location, work type, and highway
type) are used to characterize the typical traffic control figures illustrated in this manual.
Support:
Work duration is a major factor in determining the number and types of devices used in
temporary traffic control zones. The duration of a temporary traffic control zone is
defined relative to the length of time a work operation occupies a spot location.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
The four categories of work duration and their time at a location shall be:
Note:
For short-term and intermediate-term work duration, spring loaded sign mounts
and traffic drums shall be used. For long-term work duration, post mounted
signs and portable concrete barriers shall be used.
Support:
At long-term stationary temporary traffic control zones, there is ample time to install and
realize benefits from the full range of temporary traffic control procedures and devices
that are available for use. Generally, an increased number of channelizing devices,
temporary roadways, and temporary traffic barriers are used.
Standard:
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
Standard:
Support:
Most maintenance and utility operations are short-term stationary work or less. As
compared to stationary operations, mobile operations, short-duration operations, and
moderate duration operations are activities that might involve different treatments.
Devices having greater mobility might be necessary, such as signs mounted on trucks and
use of portable changeable message signs. Devices that are larger, more imposing, or
more visible can be used effectively and economically. The mobility of the temporary
traffic control zone is important. Maintaining safe work and road user conditions is a
paramount goal in carrying out mobile operations.
Guidance:
Option:
Appropriately colored or marked vehicles with rotating/strobe lights, and augmented with
signs or arrow panels may be used in place of static signs and channelizing devices for
moderate-duration, short-duration, or mobile operations.
Support:
During short-duration work, it often takes longer to set up and remove the temporary
traffic control zone than to perform the work. Workers face hazards in setting up and
taking down the temporary traffic control zone. Also, since the work time is short, delays
affecting road users are significantly increased when additional devices are installed and
removed.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
Considering these factors, simplified control procedures may be warranted for short-
duration work. A reduction in the number of devices may be offset by the use of other
more dominant devices such as rotating lights or strobe lights on work vehicles.
Support:
Mobile or short-duration operations often involve frequent short stops, each less than 15
minutes, for activities such as litter cleanup, pothole patching, or utility operations, and
are similar to short-duration operations.
Guidance:
Option:
Support:
Mobile operations also include work activities where workers and equipment move along
the road without stopping, usually at slow speeds. The advance warning area moves with
the work area.
Guidance:
When mobile operations are being performed, a shadow vehicle equipped with an arrow
panel or a sign should follow the work vehicle, especially when motor vehicle traffic
speeds or volumes are high. Where feasible, warning signs should be placed along the
roadway and moved periodically as work progresses. Under high-volume conditions,
consideration should be given to scheduling mobile operations work during off-peak
hours.
Standard:
Option:
For mobile operations that move at speeds less than three mph, mobile signs or stationary
signing that is periodically retrieved and repositioned in the advance warning area may be
used. At higher speeds, vehicles may be used as components of temporary traffic control
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zones for mobile operations. Appropriately colored and marked vehicles with signs,
rotating/strobe lights, truck-mounted attenuators, and arrow panels or portable
changeable message signs may follow a train of moving work vehicles.
For some continuously moving operations, such as street cleaning and snow removal, a
single work vehicle with appropriate warning devices on the vehicle may be used to
provide warning to approaching road users.
Standard:
Mobile operations that move at speeds greater than 20 mph, such as pavement
marking operations, shall have appropriate devices on the equipment (rotating
lights, signs, or special lighting) or shall use a separate vehicle with appropriate
warning devices.
Support:
The choice of temporary traffic control needed for a temporary traffic control zone
depends upon where the work is located and the roadway characteristics. As a general
rule, the closer the work is to road users, the greater the number of temporary traffic
control devices needed. Procedures are described later in this Section for establishing
temporary traffic control zones in the following locations:
Standard:
When the work space is within the traveled way, except for mobile operations,
advance warning shall provide a general message that work is taking place, shall
supply information about highway conditions, and shall indicate how motor vehicle
traffic can move through the temporary traffic control zone.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
Option:
Other devices may be added to supplement the devices indicated in the typical traffic
control figures, and device spacing may be adjusted to provide additional reaction time.
When conditions are less complex than those depicted in the typical traffic control
figures, fewer devices may be needed.
Guidance:
When conditions are more complex, typical application figures should be modified by
incorporating appropriate devices and practices from the following list:
A. Additional devices:
1. Signs
2. Arrow panels
3. More channelizing devices at closer spacing
4. Temporary raised pavement markers
5. High-level warning devices
6. Portable changeable message signs
7. Temporary traffic signals
8. Temporary traffic barriers
9. Crash cushions
10. Screens
11. Rumble strips
12. More delineation
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B. Upgrading of devices:
1. A full complement of standard pavement markings
2. Brighter and/or wider pavement markings
3. Larger and/or brighter signs
4. Channelizing devices with greater conspicuity
5. Temporary traffic barriers in place of channelizing devices
D. Increased distances:
1. Longer advance warning area
2. Longer tapers
E. Lighting:
1. Temporary roadway lighting
2. Steady-burn lights used with channelizing devices
3. Flashing lights for isolated hazards
4. Illuminated signs
5. Floodlights
Support:
Standard:
Support:
When work is being performed off of the roadway (beyond the shoulders, but within the
right-of-way), little temporary traffic control may be needed. Temporary traffic control
generally is not needed where work is confined to an area 30 feet or more from the edge
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of the traveled way and out of the clear zone. However, temporary traffic control is
appropriate where distracting situations exist, such as vehicles parked on the shoulder,
vehicles accessing the work site via the highway, and equipment traveling on or crossing
the roadway to perform the work operations (for example, mowing). A typical application
is shown in Figure 6H-1 of the MUTCD.
Guidance:
Where the above situations exist, a single warning sign, such as “ROAD WORK
AHEAD,” should be used. If the equipment travels on the roadway, the equipment should
be equipped with appropriate flags, rotating/strobe lights, and/or a SLOW MOVING
VEHICLE symbol. If work vehicles or equipment are on the shoulder, a “SHOULDER
WORK AHEAD” sign should be used. For mowing operations, the signs “MOWING
AHEAD” and “WATCH FOR SLOW MOVING VEHICLES” should be used.
Option:
Where the activity is spread out over a distance of more than two miles, the
“SHOULDER WORK AHEAD” sign may be repeated every one mile. A supplementary
plaque with the message “NEXT X MILES” may be used.
Guidance:
A general warning sign like “ROAD MACHINERY AHEAD” should be used if workers
and equipment must occasionally move closer to the traveled way.
Support:
Standard:
When paved shoulders having a width of eight feet or more are closed, at least one
advance warning sign shall be used. In addition, channelizing devices shall be used
to close the shoulder in advance to delineate the beginning of the work space and
direct motor vehicle traffic to remain within the traveled way.
Guidance:
When a highway shoulder is occupied, a “SHOULDER WORK AHEAD” sign, except for
short-duration and mobile operations, should be placed in advance of the activity area.
When work is performed on a paved shoulder eight feet or more in width, channelizing
devices should be placed on a taper having a length that conforms to the requirements of
a shoulder taper.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
When paved shoulders having a width of eight feet or more are closed on expressways
and freeways, road users should be warned about potential disabled vehicles that cannot
get off the traveled way. An initial general warning sign (such as “ROAD WORK
AHEAD”) should be used, followed by a “RIGHT” or “LEFT SHOULDER CLOSED
AHEAD” sign. Where the end of the shoulder closure extends beyond the distance which
can be perceived by road users, a supplementary plaque bearing the message “NEXT XX
FEET” or “MILES” or “BLOCKS” as per the functional classification of the road or as
deemed necessary by DDOT Engineer should be placed below the “SHOULDER
CLOSED AHEAD” sign. On multilane, divided highways, signs advising of shoulder
work or the condition of the shoulder should be placed only on the side of the affected
shoulder.
When the shoulder is not occupied but work has adversely affected its condition, the
“LOW SHOULDER” or “SOFT SHOULDER” sign should be used, as appropriate.
Where the condition extends over a distance in excess of one mile, the sign should be
repeated at one mile intervals.
Option:
Standard:
When used for shoulder work, arrow panels shall operate in the four-corner caution
mode only.
Support:
A typical traffic control figure for stationary work operations on shoulders is shown in
Figure 6H-3 of the MUTCD. Short-duration or mobile work on shoulders is shown in
Figure 6H-4 of the MUTCD. Work on freeway shoulders is shown in Figure 6H-5 of the
MUTCD.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
When work takes up part of a lane, motor vehicle traffic volumes, vehicle mix (buses,
trucks, and cars), speed, and capacity should be analyzed to determine whether the
affected lane should be closed. Unless the lane encroachment permits a remaining lane
width of 11 feet, the lane should be closed. Truck off-tracking should be considered when
determining whether the minimum lane width of 10 feet is adequate when working on exit
ramps.
Option:
A lane width of 10 feet may be used for short-term stationary work on low-volume (less
than 500 vehicles per day), low-speed (under 45 mph) roadways when motor vehicle
traffic does not include longer and wider heavy commercial vehicles.
Support:
Figure 6H-6 of the MUTCD illustrates a method for handling motor vehicle traffic where
the stationary or short duration work space encroaches slightly into the traveled way.
Guidance:
If work in the median of a divided highway is within 15 feet from the edge of the traveled
way for either direction of travel, or within the clear zone, temporary traffic control
should be used through the use of advance warning signs and channelizing devices.
Support:
Detour signs are used to direct road users onto another roadway. At diversions, road users
are directed onto a temporary roadway or alignment placed within or adjacent to the
right-of-way. Examples of typical applications for detouring or diverting road users on
two-lane highways can be found in Figures 6H-7, 6H-8, and 6H-9 of the MUTCD.
Standard:
Detours and diversions shall be reviewed and approved by the DDOT Engineer
prior to implementation.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Guidance:
When a detour is long, Detour Marker (M4-8) or Detour (M4-9) signs should be installed
to remind and reassure road users periodically that they are still successfully following
the detour. When an entire roadway is closed, a detour should be provided and road
users should be warned in advance of the closure. If local road users are allowed to use
the roadway up to the closure, the “ROAD CLOSED TO THRU TRAFFIC” sign should
be used. The portion of the road open to local road users should have adequate signing,
marking, and delineation. Detours should be signed so that road users will be able to
traverse the entire detour route and return to the original roadway.
Option:
Flaggers may be used as shown in Typical Application for Lane Closures on a Minor
Street (Figure9-6).
Support:
In urban temporary traffic control zones, decisions are needed on how to control motor
vehicle traffic, such as how many lanes are required, whether any turns should be
prohibited at intersections, and how to maintain access to business, industrial, and
residential areas. Pedestrian traffic needs separate attention. A separate section devoted to
pedestrian and worker safety contains information regarding controlling pedestrian
movements near work zones.
Standard:
If the temporary traffic control zone affects the movement of pedestrians, adequate
pedestrian access and walkways shall be provided. If the temporary traffic control
zone affects the movement of bicyclists, adequate access to the roadway, bicycle
paths, or shared-use paths shall be provided (see Part 9 of the MUTCD for
additional guidance).
Guidance:
If a designated bicycle route is closed because of the work being done, a signed alternate
route should be provided. Bicyclists should not be directed onto the path used by
pedestrians.
Support:
Utility work takes place both within and outside the roadway to construct and maintain
services such as power, gas, light, water, or telecommunications. Operations often
involve intersections, since that is where many of the network junctions occur. The work
force is usually small, only a few vehicles are involved, and the number and types of
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
temporary traffic control devices placed in the temporary traffic control zone is usually
minimal.
Standard:
Guidance:
Support:
Work on multilane (two or more lanes in one direction) highways is divided into right-
lane closures, left-lane closures, interior-lane closures, multiple-lane closures, and
closures on five-lane roadways.
Standard:
Guidance:
Standard:
When temporary traffic barriers are placed immediately adjacent to the traveled
way, they shall be equipped with appropriate channelizing devices, delineation,
and/or other temporary traffic control devices. For lane closures, the merging taper
shall use channelizing devices and the temporary traffic barrier shall be placed
beyond the transition area.
Support:
It must be recognized that although temporary traffic barriers are shown in several of the
typical applications in this manual, they are not considered to be temporary traffic control
devices in themselves.
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Figure 6H-34 of the MUTCD illustrates a lane closure in which temporary traffic barriers
are used.
1. To keep motor vehicle traffic from entering work areas, such as excavations or
material storage sites
2. To separate workers, bicyclists, and pedestrians from motor vehicle traffic
3. To separate opposing directions of motor vehicle traffic
4. To separate motor vehicle traffic, bicyclists, and pedestrians from the work area such
as false work for bridges and other exposed objects
Option:
When the right lane is closed, temporary traffic control similar to that shown in Figure
6H-34 of the MUTCD may be used for undivided or divided 4-lane roads.
Guidance:
If morning and evening peak hourly motor vehicle traffic volumes in the two directions
are uneven and the greater volume is on the side where the work is being done in the
right lane, consideration should be given to closing the inside lane for opposing motor
vehicle traffic and making the lane available to the side with heavier motor vehicle
traffic. If the larger motor vehicle traffic volume changes to the opposite direction at a
different time of the day, the temporary traffic control should be changed to allow two
lanes for opposing motor vehicle traffic by moving the devices from the opposing lane
back to the centerline. When it is necessary to create a temporary centerline that is not
consistent with the pavement markings, channelizing devices should be used and closely
spaced.
Support:
Peak Hours in the District of Columbia are defined as the hours of 6:30 a.m. to 9:30 a.m.
and 3:30 p.m. to 6:30 p.m., Monday through Friday, except holidays. “Off-peak hours”
occur during those hours and days not identified as “peak hours.”
Option:
When closing a left lane on a multilane undivided road, as motor vehicle traffic flow
permits, the two interior lanes may be closed to provide motorists and workers additional
lateral clearance and to provide access to the work space.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Standard:
When only the left lane is closed on undivided roads, channelizing devices shall be
placed along the centerline as well as along the adjacent lane.
Guidance:
When an interior lane is closed, an adjacent lane should also be considered for closure
(when available and practical) to provide additional space for vehicles and materials and
to facilitate the movement of equipment within the work space. When multiple lanes in
one direction are closed, a capacity analysis should be made to determine the number of
lanes needed to accommodate motor vehicle traffic needs. Motor vehicle traffic should be
moved over one lane at a time. As shown in Figure 6H-37 of the MUTCD, the tapers
should be separated by a distance of 2L, with L being determined by the formulas in
Table 4-2.
Standard:
Option:
When half the road is closed on an undivided highway, both directions of motor vehicle
traffic may be accommodated as shown in Figure 6H-32 of the MUCTD. When both
interior lanes are closed, temporary traffic controls may be used as indicated in Figure
6H-37 of the MUTCD for both directions of travel. When a roadway must be closed on a
divided highway, a median crossover may be used.
Support:
Temporary traffic control for lane closures on 5-lane roads is similar to other multilane
undivided roads. Figure 6H-32 of the MUTCD can be adapted for use on 5-lane roads.
Support:
The typical traffic control applications for intersections are classified according to the
location of the work space with respect to the intersection area (as defined by the
extension of the curb or edge lines). The three classifications are near side, far side, and
in-the-intersection. Work spaces often extend into more than one portion of the
intersection. For example, work in one quadrant often creates a near-side work space on
one street and a far-side work space on the cross street. In such instances, an appropriate
temporary traffic control plan is obtained by combining features shown in two or more of
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
the intersections and pedestrian typical applications. Temporary traffic control zones in
the vicinity of intersections might block movements and interfere with normal road user
flows. Such conflicts frequently occur at more complex signalized intersections having
such features as traffic signal heads over particular lanes, lanes allocated to specific
movements, multiple signal phases, and signal detectors for actuated control.
Guidance:
The effect of the work upon signal operation should be considered, such as signal
phasing for ensuring adequate capacity, maintaining or adjusting signal detectors, and
ensuring the appropriate visibility of signal heads.
Standard:
When work will occur near signalized intersections where operational and capacity
problems are anticipated, DDOT shall be contacted.
Guidance:
When work will occur near non-signalized intersections where operational and capacity
problems are anticipated, the highway agency having jurisdiction should be contacted.
For work at an intersection, advance warning signs, devices, and markings should be
used on all cross streets, as appropriate. The typical traffic control figures depict urban
intersections on arterial streets. Where the posted speed limit, the off-peak 85th-percentile
speed prior to the work starting, or the anticipated speed exceeds 40 mph, additional
warning signs should be used in the advance warning area.
Support:
Near-side work spaces, as depicted in Figure 6H-21 of the MUTCD, are simply handled
as a midblock lane closure. A problem that might occur with near-side lane closure is a
reduction in capacity, which during certain hours of operation could result in congestion
and backups.
Option:
When near-side work spaces are used, an exclusive turn lane may be used for through
motor vehicle traffic. Where space is restricted in advance of near-side work spaces, as
with short block spacing, two warning signs may be used in the advance warning area,
and a third action-type warning or regulatory sign (such as “KEEP LEFT”) may be
placed within the transition area.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
Far-side work spaces, as depicted in Figures 9-9 and 9-10 of the Typical Applications,
involve additional treatment because road users typically enter the activity area by
straight-through and left- or right-turning movements.
Guidance:
When a lane through an intersection must be closed on the far side, it should also be
closed on the near-side approach to preclude merging movements within the intersection.
Option:
If, however, there are a significant number of vehicles turning from a near-side lane that
is closed on the far side, the near-side lane may be converted to an exclusive turn lane.
Support:
Figures 9-11 through 9-14 of the Typical Applications provide guidance on applicable
procedures for work performed within the intersection.
Option:
If the work is within the intersection, any of the following strategies may be used:
A. A small work space so that road users can move around it, as shown in Figure 9-11
Guidance:
Support:
Problems of temporary traffic control might occur under the special conditions
encountered where motor vehicle traffic must be moved through or around temporary
traffic control zones on high-speed, high-volume roadways. Although the general
principles outlined in the previous Sections of this Manual are applicable to all types of
highways, high-speed, access-controlled highways need special attention in order to
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
safely and efficiently accommodate motor vehicle traffic while also protecting work
forces. The road user volumes, road vehicle mix (buses, trucks, and cars), and speed of
vehicles on these facilities require that careful temporary traffic control procedures be
implemented, for example, to induce critical merging maneuvers well in advance of work
spaces and in a manner that creates minimum turbulence and delay in the motor vehicle
traffic stream. These situations often require more conspicuous devices than specified for
normal rural highway or urban street use. However, the same important basic
considerations of uniformity and standardization of general principles apply for all
roadways.
Temporary traffic control for a typical lane closure on a divided highway is shown in
Figure 6H-33 of the MUTCD. Temporary traffic controls for short duration and mobile
operations on freeways are shown in Figure 6H-35. A typical application for shifting
motor vehicle traffic lanes around a work space is shown in Figure 6H-36 of the
MUTCD. Temporary traffic controls for multiple and interior lane closures on a freeway
are shown in Figure 6H-38 of the MUTCD.
Guidance:
The method for closing an interior lane when the open lanes have the capacity to carry
motor vehicle traffic should be as shown in Figure 6H-38 of the MUTCD.
Support:
Standard:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
with channelizing devices throughout the length of the two-way operation. The use
of markings and complementary signing, by themselves, shall not be used.
Support:
Figure 6H-39 of the MUTCD shows the procedure for two-lane, two-way operation.
Treatments for entrance and exit ramps within the two-way roadway segment of this type
of work are shown in Figures 6H-40 and 6H-41 of the MUTCD. Modifications to any of
these layouts must first be reviewed and approved by the DDOT Engineer prior to their
usage.
8.11 CROSSOVERS
Guidance:
The following are considered good guiding principles for the design of crossovers:
Support:
Temporary traffic barriers and the excessive use of temporary traffic control devices
cannot compensate for poor geometric and roadway cross-section design of crossovers.
8.12 INTERCHANGES
Guidance:
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Option:
If access is not possible, ramps may be closed by using signs and Type III barricades. As
the work space changes, the access area may be changed, as shown in Figure 6H-42 of
the MUTCD. A temporary traffic control zone in the exit ramp may be handled as shown
in Figure 6H-43. When a work space interferes with an entrance ramp, a lane may need to
be closed on the freeway. A temporary traffic control zone in the entrance ramp may
require shifting ramp motor vehicle traffic. Temporary traffic control for both operations
is shown in Figure 6H-44 of the MUTCD.
Support:
Figure 6H-45 of the MUTCD shows a temporary reversible lane using movable barriers.
Standard:
Option:
If the work activity in Figure 6H-45 of the MUTCD permits, a movable barrier may be
used and relocated to the shoulder during non-work periods or peak-period motor vehicle
traffic conditions.
Standard:
When highway-rail grade crossings exist either within, or in the vicinity of, a
temporary traffic control zone, lane restrictions, flagging, or other operations shall
not create conditions where vehicles can be stopped on the railroad tracks with no
means of escape. If the queuing of vehicles across the tracks cannot be avoided, a
law enforcement officer or certified flagger shall be provided at the crossing to
prevent vehicles from stopping on the tracks, even if automatic warning devices are
in place.
Support:
Figure 6H-46 of the MUTCD shows work in the vicinity of a highway-rail grade
crossing.
Guidance:
Early coordination with the railroad company should occur before work starts.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
Guidance:
In order to reduce response time for incident management, highway agencies and
municipalities should preplan for occurrences of incidents along the major and heavily
traveled highway and street system. Special events should be planned for and
coordinated in advance.
Support:
While some incidents might be anticipated and planned for, emergencies and disasters
might pose more severe and unpredictable problems. The ability to install proper
temporary traffic control might greatly reduce the effects of an emergency. An essential
part of fire, rescue, spill clean-up, and enforcement activities is the proper control of road
users through the incident area. These operations need corroborating legislative authority
for the implementation and enforcement of appropriate road user regulations, parking
controls, and speed zoning. It is desirable for these statutes to provide sufficient
flexibility in the authority for and implementation of temporary traffic control to respond
to the needs of changing conditions found in incident areas.
Option:
Standard:
If the incident is anticipated to last more than three days, applicable procedures and
devices set forth in this manual shall be used.
Support:
A short-term road closure can be caused by an incident such as a road user crash that
blocks the traveled way. Road users are usually detoured around the incident and back to
the original roadway. A combination of traffic engineering and enforcement preparations
is needed to determine the detour route and install the necessary devices. Large trucks are
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
a significant concern in such a detour. During incidents, large trucks might need to follow
a route separate from that of automobiles because of bridge, weight, clearance, or
geometric restrictions. Also, vehicles carrying hazardous cargo might need to follow a
different route from other vehicles.
Some incidents such as hazardous spills might require closure of an entire highway.
Through road users must have adequate guidance around the incident. Maintaining good
public relations is desirable. The cooperation of the news media in publicizing the
existence of and reasons for incident areas and their temporary traffic control can be of
great assistance in keeping road users and the general public well informed.
Guidance:
The channelizing devices discussed in the previous section should be used whenever
possible. When flares are used to initiate temporary traffic control at incidents or for
short-term temporary traffic control, they should be replaced by more permanent devices
as soon as practical. Both the flare and its supporting device should be removed from the
roadway.
Support:
Inclement weather (rain, snow, fog, etc.) creates the following conditions for road users:
lack of visibility to the road and temporary traffic control devices; greater distance
required to slow and stop a motor vehicle; an increase in the difficulty of controlling a
motor vehicle; and an increase in distraction and anxiety for road users while traveling on
the roadway.
Guidance:
Option:
Emergency operations, however, may be performed where inaction would be worse than
allowing the condition to remain unattended.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Support:
The diagrams on the following pages represent examples of the application of principles
and procedures for safe and efficient traffic control in temporary traffic control zones and
are not intended to be standards. It is not possible to include illustrations to cover every
situation which will require work area protection. These typical layouts area not intended
as a substitute for engineering judgment and should be altered to fit the conditions of a
particular site. Contractor plans or other agency documents may also have applicable
layouts to be followed.
The diagrams are not to scale, and the number of channelizing devices shown may not be
the number needed at the work site. The tables on the typical applications are to be used
to determine taper and buffer lengths, using Section 7 for guidance on the spacing and
number of devices.
Notes and tables found throughout Section 9 provide information for the development of
temporary traffic control zones. Read all notes before using these diagrams.
In general, the procedures illustrated represent minimum solutions for the situations
depicted. For further information, refer to Part 6 of the MUTCD. It contains the standards
for work zone traffic control, including sign type numbers and dimensions of signs.
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9-2
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Arrow panel
Channelizing Device
Direction of traffic
Flagger
Illuminated Flashing
Amber (caution Mode)
Type B or C
Traffic Signal
Work Zone
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
A Road Work Ahead sign should be placed on the left side of the roadway for a divided
or one-way street only if the left shoulder is affected.
The Worker Symbol (W21-1) signs may be used instead of Road Work Ahead signs.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
9-5
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
In those situations where multiple work locations within a limited distance make it
practical to place stationary signs, the distance between the advance warning sign and the
work should not exceed one block in urban low-speed areas or one mile on high-speed
roads.
Each vehicle involved in the mobile operation shall have at least one rotating amber light
or high intensity amber strobe light.
“Utility Work Ahead” may be used in low-speed urban areas or “Shoulder Work Ahead”
may be used along highways with shoulders.
72-hour advanced parking restrictions are required for mobile operations, except in the
event of an emergency.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
PARKING / OUTER
LANES
50'-100'
TRUCK MOUNTED
ATTENUATOR
(OPTIONAL)
SEE NOTE 4
PARKING / OUTER
LANES ILLUMINATED FLASHING
AMBER (CAUTION MODE)
TYPE B OR C
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Vehicle-mounted signs shall be mounted with the bottom of the sign at a minimum height
of 48 inches above the pavement. Sign legends shall be covered or turned from view
when work is not in progress.
Shadow and work vehicles shall display rotating lights or strobe lights.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
In those situations where multiple work locations within a limited distance make it
practical to place stationary signs, the distance between the advance warning sign and the
work should not exceed one block in urban low-speed areas or one mile on high-speed
roads.
This application is shown where encroachment occurs in the parking lane or curb lane. In
cases where there are shoulders, the “Right Lane Closed Ahead” sign will be replaced
with a “Shoulder Work” sign (i.e. on divided high-speed highways). Spacing will vary
depending on road classification type and speed. Refer to Part 6 of the MUTCD.
Each vehicle involved in the mobile operation shall have at least one rotating amber light
or high intensity amber strobe light.
Any situation or location that requires more than three days of lane closures or impacts
requires installation of temporary pavement markings.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Where buses are permitted, the lanes on either side of the center work space should have
a minimum width of 11 feet as measured from the near edge of the channelizing devices
to the edge of pavement or the outside edge of paved shoulder.
Flashing warning lights and/or flags may be used to call attention to the advanced
warning signs.
If the closure continues overnight, warning lights may be used on the channelizing
devices.
A lane width of 10 feet may be used for short-term stationary work on low-volume, low-
speed roadways when motor vehicle traffic does not include longer and wider heavy
commercial vehicles and where buses are restricted.
A work vehicle displaying rotating lights or strobe lights may be used instead of the
channelizing devices forming the tapers or the high-level warning devices.
Although vehicle hazard warning signals can be used to supplement the rotating light or
strobe lights, they shall not be used instead of rotating lights or strobe lights.
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This temporary traffic control shall be used only for low-volume, low-speed facilities.
When motor vehicle traffic cannot effectively self-regulate, one or two flaggers shall be
used.
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This layout is appropriate for city streets and local roadways. See Figure 6H-8 or 6H-9 of
Part 6 of the MUTCD for closing and detouring a numbered highway.
When used, the Street Name sign shall be placed above the Detour sign.
When a side road intersects the roadway within the work zone, place Type III barricades
and ROAD CLOSED signs at the intersection, and provide advance signing of the closure
on the side road approaches.
DETOUR signs may be located on the far side of the intersections, provided the
intersection width does create a sight distance issue.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
This layout is appropriate for city streets and local roadways. See Figure 6H-8 or 6H-9 of
Part 6 of the MUTCD, for closing and detouring a numbered highway.
When used, the Street Name sign shall be placed above the Detour sign.
When a side road intersects the roadway within the work zone, place Type III barricades
and ROAD CLOSED signs at the intersection and provide advance signing of the closure
on the side road approaches.
DETOUR signs may be located on the far side of the intersections, provided the
intersection width does create a sight distance issue.
The District Fire Marshall must give approval prior to the beginning of work on this type
of application.
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Figure 9-8. Typical Application: Road Closure and Detour for Two Travel
Directions
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
The normal procedure is to close, on the near side of the intersection, any lane that is not
carried through the intersection. However, when this results in the closure of a right lane
having significant right-turning movements, the right lane may be restricted to right turns
only. This procedure increases the through capacity by eliminating right turns from the
open through lane.
If the work space extends across a crosswalk, the crosswalk should be closed using the
procedures and methods shown at the end of these typical applications (see Sidewalk
Closure and Bypass Sidewalk Operation).
When the turning radius is large, it may be possible to create a right-turn island using
channelizing devices.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Figure 9-9. Typical Application: Right Lane Closure at Far Side of the Intersection
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
The normal procedure is to close, on the near side of the intersection, any lane that is not
carried through the intersection. However, when this results in the closure of a left lane
having significant left-turning movements, the left lane may be reopened as a turn bay for
left turns only, as shown. This procedure increases the through capacity by eliminating
left turns from the open through lane.
If the work space extends across a crosswalk, the crosswalk should be closed using the
procedures and methods shown at the end of these typical applications (see Sidewalk
Closure and Bypass Sidewalk Operation).
If heavy through movements typically utilize the left lane, channelization devices should
be used to close off the left lane with a taper and then the lane may be reopened, as
shown in Figure 6H-23 in Part 6 of the MUTCD.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Figure 9-10. Typical Application: Left Lane Closure at Far Side of the Intersection
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
If the work space extends across a crosswalk, the crosswalk should be closed using the
procedures and methods shown at the end of these typical applications (see Sidewalk
Closure and Bypass Sidewalk Operation).
If the left through lane is closed on the near-side approach, the LEFT LANE MUST
TURN LEFT sign should be placed in the median to discourage through vehicular traffic
from entering the left-turn bay.
If the situation or location remains under construction for greater than three days, the
KEEP RIGHT is replaced with an R4-7 sign.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
A high-level warning device may be placed in the work space if there is sufficient room.
For short-term use on low-volume, low-speed roadways, with vehicular traffic that does
not include heave commercial vehicles or buses, a minimum of 10 feet may be used.
Unless the streets are wide, it may be physically impossible to turn left, especially for
large vehicles. Left turns may be prohibited as required by geometric conditions.
If the situation or location remains under construction for greater than three days, the
KEEP RIGHT is replaced with an R4-7 sign.
The arrow panel should be placed as close to the beginning of the taper as possible and as
space allows.
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The situation depicted may be simplified by closing one or more of the intersection
approaches. If this cannot be done and/or when capacity is a problem, through vehicular
traffic should then be directed to other roads or streets.
Turns can be prohibited as required by vehicular traffic conditions. Unless the streets are
wide, it might be physically impossible to make certain turns, especially for commercial
vehicles or buses.
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The situation depicted may be simplified by closing one or more of the intersection
approaches. If this cannot be done and/or when capacity is a problem, through vehicular
traffic should then be directed to other roads or streets.
Turns can be prohibited as required by vehicular traffic conditions. Unless the streets are
wide, it might be physically impossible to make certain turns, especially for commercial
vehicles or buses.
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The closure of the adjacent interior lane in the opposing direction may not be necessary,
depending upon the activity being performed and the work space needed for the
operation.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Except for soft-term durations, temporary markings shall be provided to clearly delineate
the temporary travel path. Pavement markings no longer applicable shall be removed or
obliterated as soon as practical. For short-term situations where it is not feasible to
remove and restore pavement markings, channelization shall be made dominant by using
very close device spacing.
When channelization devices are used instead of pavement markings, the maximum
spacing should be 0.5 x S feet, where S is the speed in mph.
If the tangent distance along the temporary diversion is more than 600 feet, a Reverse
Curve sign, left first, should be used instead of the Double Reverse Curve sign, and a
second Reverse Curve sign, right first, should be placed in advance of the second reverse
curve back to the original alignment.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
A high-level warning device should be placed in the work space if there is sufficient
room.
For short-term use on low-volume, low-speed roadways, with vehicular traffic that does
not include heavy commercial vehicles or buses, a minimum of 10 feet may be used.
Unless the streets are wide, it may be physically impossible to turn left, especially for
large vehicles. Left turns may be prohibited as required by geometric conditions.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Bypass Sidewalk Operations must account for use by wheelchairs or provide an alternate
means of conveyance for pedestrians with disabilities.
Only the Temporary Traffic Control devices related to pedestrians are shown. Other
devices, such as lane closure signing or ROAD NARROWS signs, may be used to control
vehicular traffic.
Signs, such as KEEP RIGHT (or LEFT), may be placed along a temporary sidewalk to
guide or direct pedestrians.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
Curb parking shall be prohibited for at least 50 feet in advance of the mid-block
crosswalk.
Only the Temporary Traffic Control devices related to pedestrians are shown. Other
devices, such as lane closure signing or ROAD NARROWS signs, may be used to control
vehicular traffic.
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D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
When placing a dumpster, it must be set back a minimum of 50 feet from the corner of
both adjacent intersection approaches.
1. For all dumpster permit requests exceeding 14 days, using the third party system,
the application permit shall be sent electronically or by fax to DDOT Traffic
Services Administration for approval.
2. For all Crane permit requests for more than three consecutive days, DDOT Public
Space Administration shall electronically notify DDOT TSA immediately with a
copy of the permit or by fax and application.
Dumpsters are permitted on the main thoroughfares (commuter routes) from 9:30 a.m. to
3:00 p.m. and 10:00 p.m. to 5:00 a.m. ONLY. If the roadway is marked with “NO
STANDING / NO PARKING ANYTIME” or “NO STOPPING 7 am to 9:30 am and 4
pm to 6:30 pm MONDAY – FRIDAY NO PARKING ALL OTHER TIMES” signs,
dumpsters are not allowed any time.
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Standard:
For all crane permit requests for more than three consecutive days, DDOT Public
Space Administration shall electronically notify DDOT TSA immediately with a
copy of the permit or by fax and application.
Support:
Considerations for crane selection should include the weights, dimensions and lift radii
expected, the type of lifting to be done, the serviceability of the equipment and the site
conditions.
1. 40 Ton Crane
2. 50 Ton Crane
3. 70 Ton Crane
4. 120 Ton Crane
5. 150 Ton Crane
6. 220 Ton Crane
When using a particular crane, state the reason why this crane is used over another type
of crane size.
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Standard:
• Entire street must be closed within the block where crane is to be used.
For cranes 220 tons and above, a special use permit is required.
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Support:
The diagrams on the following pages represent examples of the application of principles
and procedures for safe and efficient traffic control in temporary traffic control zones and
are not intended to be standards. It is not possible to include illustrations to cover every
situation which will require work area protection. These typical layouts area not intended
as a substitute for engineering judgment and should be altered to fit the conditions of a
particular site. Contractor plans or other agency documents may also have applicable
layouts to be followed.
The diagrams are not to scale, and the number of channelizing devices shown may not be
the number needed at the work site. The tables on the typical applications are to be used
to determine taper and buffer lengths, using Section 7 for guidance on the spacing and
number of devices.
Notes and tables found throughout Section 10 provide information for the development of
temporary traffic control zones. Read all notes before using these diagrams.
In general, the procedures illustrated represent minimum solutions for the situations
depicted. For further information, refer to Part 6 of the MUTCD. It contains the standards
for work zone traffic control, including sign type numbers and dimensions of signs..
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Figure 10-7. Crane Typical for a Two-Way St./Two Lane Closure/Lane Shift TCP 1
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Figure 10-9. Typical Details for a One-Way St. Two Lane Closure TCP 3
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Figure 10-10. Typical Detail for a Two-Way St. One Lane Closure/Flagger
Operation TCP 4
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Figure 10-11. Crane Typical for a Two-Way St. Right Lane Closure TCP 5
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APPENDICES
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
APPENDIX A
The roadway network in the District of Columbia is arrayed into a system of categories
that represent the use and function of each street. This system is called the Functional
Classification of Streets. The functional categories range from Principal Arterials, which
are major traffic carriers in the city, to Local Streets, which serve predominantly local
traffic and carry little to no through traffic. The street network is classified for a number
of reasons. The primary reason is to assure that street improvement funds are allocated in
a manner that ensures that those streets that are most important in maintaining the daily
flow of people and goods throughout the city are given priority for construction funding.
The classifications also play an important role in traffic planning. A goal of traffic
planning is to funnel as much traffic as possible onto the major arteries in the city and
discourage traffic from using the narrow neighborhood streets that comprise the major
portion of the city network. The classification system details the extent to which streets
are functioning as traffic carriers and is therefore used as a framework for planning such
improvements as traffic signa1ization channelizations and various sign and pavement
marking details. These classifications can be used in determining which streets are
candidates for traffic restraints.
The street network is split into four categories and three sub-categories. They are:
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A brief description of each category and/or the common characteristics of streets in each
category follows:
Other Principal Arterials - These streets are the primary, non-freeway traffic carriers in
the city. They provide the linkage for the District with the surrounding jurisdictions and
beyond and also provide the connections for major cross-town and intra-city movements.
A typical other principal arterial is Rhode Island Avenue, N.E. It is six 1anes wide with
non-rush hour on-street parking and carries over 25,000 vehicles per day.
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Minor arterials - These streets provide the connections between the principal arterial
networks and may service major flows in an area with no clearly defined principal arterial
street. The characteristics of streets in this classification are:
A typical minor arterial is Piney Branch Road, N.W. which carries two lanes of traffic in
the peak period and one lane at all other times. It carries 15,000 vehicles per day.
Collectors - These streets serve a variety of functions, including providing direct access
to major traffic generators, i.e. a METRO station or a large complex of apartments. They
may be a connection from a neighborhood to the arterial network or may provide a
connection between arterial streets in an area where no clearly defined minor arterial is
present to handle the connection. The characteristics of streets in this classification are:
A typical collector is Fort Lincoln Drive, N.E., which provides access into the Fort
Lincoln New Town Development.
Local streets - These roadways provide direct access to abutting lane use with a
minimum of through traffic. Traffic volumes are less than 2,000 vehicles per day and bus
and truck use is only to provide local service or delivery. By definition local streets
comprise all streets not on a higher category.
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The first two sub-categories of Principal arterials are defined by their construction. Both
Interstate and Other Freeways are unique in their physical characteristics. They are
controlled access facilities; that is, access to the roadway is usually by a ramp and/or an
interchange. There are generally no intersections or traffic signals, no parking, or
driveways to adjoining land use. The remaining classifications are comprised of city
streets that are assigned to a category based on a combination of physical and operational
characteristics. Each street is assigned after a review of the pertinent data for each
section. The date includes street width, number of lanes, traffic volumes (both peak and
off peak), bus routes, parking regulations, land use, and the relationship of the street with
the regional and city roadway network. The classifications are based on use, and
therefore existing travel patterns play a major role in the determination of the
classification assigned. The data assembled for each street is compared to the desired
characteristics for each classification (listed in previous section) and assignments are
made accordingly.
Use and extent of each system - A primary goal in traffic planning is to accommodate as
much traffic as practical on a minimum mileage of streets. The D.C. street systems'
operation in this regard is demonstrated in Table 1, which details the proportional use of
the street network by each functional classification.
Table 1
Proportion of
Functional Classification Miles/ (% of Total) Daily Traffic
This demonstrates the effectiveness of the present system, as the Principal arterial
network, which comprises only 12 percent of the roadway mileage, carries 51 percent of
the traffic and the local street system which is the major portion of the D.C. network,
carries less than 10 percent of the traffic in the City.
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APPENDIX B
This document is prepared to provide users of approved Traffic Control Plans (TCPs) the
criteria that the field implementation of their TCPs will be evaluated against the District
Department of Transportation (DDOT) will periodically inspect work zones to ensure
compliance, verify that safety measures are in place, and ascertain that the measures
conform to the approved TCP and criteria listed below:
1. CONTRACTOR SHALL HAVE, AT ALL TIMES, COPIES OF THEIR TCPs & PERMIT ON
SITE AND AVAILABLE FOR THE INSPECTOR’S REVIEW. UNLESS OTHERWISE
AUTHORIZED BY DDOT, ANY PROJECT / CONTACTOR FAILING TO HAVE APPROVED
PERMITS AND TCPs ON SITE, OR ANY CONTRACTOR FAILING TO FOLLOW THE
APPROVED PLAN AND TCP, WILL BE SUBJECT TO FINES AND POSSIBLE IMMEDIATE
SUSPENSION OF WORK.
2. ALL TRAFFIC CONTROL SHALL CONFORM TO PART VI OF THE 2003 EDITION MANUAL
ON UNIFORM TRAFFIC CONTROL DEVICES (MUTCD) AND DDOT’S WORK ZONE
MANUAL. ALL TRAFFIC CONTROL DEVICES SHOULD COMPLY WITH NCHRP 350
CRASH TESTING STANDARDS AND SHOULD HAVE MARKINGS OF COMPLIANCE ON
THE STANDARDS.
3. THE CONTRACTOR SHALL MAKE CERTAIN THAT THE PERSON(S) RESPONSIBLE FOR
THE IMPLEMENTATION OF THE TRAFFIC CONTROL PLAN HAS SUCCESSFULLY
COMPLETED TRAINING IN TEMPORARY TRAFFIC CONTROL AND HIS OR HER NAME
AND QUALIFICATIONS SHALL BE SUBMITTED PRIOR TO WORK COMMENCING.
ACCEPTED CERTIFYING ORGANIZATIONS ARE ATSSA, MDOT, VDOT, OR
EQUIVALENT.
4. ALL FIELD PERSONNEL SHALL WEAR SAFETY VEST, HARD HATS, AND OTHER
REQUIRED PERSONAL PROTECTION EQUIPMENT.
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7. CONTRACTORS SHALL NOT CLOSE MORE THAN ONE LANE OF TRAFFIC IN ONE
DIRECTION UNLESS OTHERWISE APPROVED.
8. ARROW PANELS ARE REQUIRED FOR LANE CLOSURES ON MAJOR ARTERIALS AND
MAY BE DEEMED NECESSARY ON OTHER ROADWAYS.
10. TYPE III BARRICADES SHALL BE USED FOR ROAD CLOSURES. ADEQUATE ROAD
CLOSURE AND DETOUR SIGNAGE SHALL BE INSTALLED TO GIVE MOTORIST
GUIDANCE. DETOUR DIRECTION SIGNS MUST BE ACCOMPANED BY MESSAGE
SIGNS THAT INDICATE DETOUR STREET NAME. DO NOT USE ABBREVIATIONS ON
MESSAGE SIGNS.
11. ALL LEADING ENDS OF THE TEMPORARY CONCRETE BARRIERS EXPOSED TO ON-
COMING TRAFFIC SHALL BE PROTECTED WITH PORTABLE IMPACT QUADGUARD
TRAFFIC ATTENUATOR. ALL ATTENUATORS SHALL HAVE OBJECT MARKERS.
12. CONTRACTORS SHALL INSTALL “STEEL PLATE AHEAD” SIGNS WHENEVER PLATES
HAVE BEEN INSTALLED.
14. DAYTIME WORK HOURS ARE BETWEEN 9:30 A.M. - 3:30 P.M. OR AS APPROVED.
15. NIGHTTIME WORK HOURS ARE BETWEEN 7:30 P.M. - 4:30 A.M. OR AS APPROVED.
19. ALL CONSTRUCTION VEHICLES OPERATING IN AND AROUND THE WORK ZONE
SHALL OPERATE STROBE OR REVOLVING LIGHTS AT ALL TIMES. THESE LIGHTS
SHOULD BE MOUNTED IN SUCH A MANNER THAT THEY ARE VISIBLE 360 DEGREES.
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28. CONTRACTOR MAY BE REQUIRED TO HIRE POLICE FOR PARKING AND WORK ZONE
ENFORCEMENT.
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31. ALL TRAFFIC CONTROL DEVICES NOT IN USE SHALL BE REMOVED FROM THE
PUBLIC SPACE OR AS DIRECTED BY DDOT. WHEN APPROVED BY DDOT ALL
REGULATORY SIGNS MUST BE COVERED SECURELY TO AVOID MISINFORMATION.
32. PORTABLE CHANGEABLE MESSAGE SIGNS (PCMS) MAY BE REQUIRED TO GIVE THE
MOTORING PUBLIC ADVANCE NOTIFICATION OF ROAD CONDITIONS, ROADWORK,
AND/OR EVENTS. ARROW BOARDS MAY ALSO BE REQUIRED IN WORK ZONES TO
AID IN LANE CLOSURES AND, WHERE WORK REQUIRES, A TRUCK MOUNTED
ATTENUATOR (TMA) CAN BE REQUIRED AS WORK DICTATES.
34. WHEN REQUIRED BY DDOT, THE CONTRACTOR MAY BE REQUIRED TO LOWER THE
POSTED SPEED LIMIT IN THE WORK ZONE DURING THE LIFE OF THE PROJECT. ALL
CHANGES TO REGULATORY SIGNS WILL BE INDICATED TO THE PUBLIC WITH THE
ADDITION OF TWO ORANGE WORKZONE FLAGS, AND WHEN REQUIRED BY DDOT, A
TYPE B LIGHT MAY BE NECESSARY.
35. “END CONSTRUCTION” AND “ROAD WORK AHEAD” SIGNS WILL BE REQUIRED AT
THE ENDS OF THE WORK ZONE; THIS INCLUDES ANY STREETS AFFECTED THAT
WILL LEAD INTO OR OUT OF THE WORK AREA.
37. THE TEMPORARY SIGNS AND MARKINGS PLACED ADJACENT TO THE WORK ZONE
SHALL BE CONSISTENT AND VISIBLE AT ALL TIMES.
38. DURING NIGHTTIME HOURS, THE WORK SITE SHALL BE MADE SAFE FOR TRAFFIC.
WARNING SHALL BE PROVIDED BY INSTALLING ELECTRONICALLY ILLUMINATED
TRAFFIC CONTROL DEVICES SUCH AS FLASHING ARROW PANELS AND WARNING
LIGHTS. THESE DEVICES SHOULD BE USED IN CONJUNCTION WITH OTHER TRAFFIC
CONTROL DEVICES, AND THEIR FLASHING SEQUENCE AND LIGHT INTENSITY SHALL
MEET THE REQUIREMENTS CITED IN THE MUTCD. ALL TRAFFIC CONTROL DEVICES
MUST BE REFLECTORIZED DURING NIGHTTIME HOURS.
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41. THE CONTRACTOR SHALL GIVE 72 HOURS PRIOR NOTICE TO THE DDOT/TSA WHEN
MAKING A CHANGE IN TRAFFIC FLOW PATTERNS.
If you have questions or need further information, please contact Traffic Services
Administration at (202) 671-2710.
Our goal is a safe work zone. Thank you for your cooperation!
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GENERAL
TRAFFIC CONTROL PLAN (TCP) SUBMITTAL GUIDELINES
(APPLICATIONS FOR PUBLIC SPACE PERMITS ONLY)
This document provides guidance for Traffic Control Plan submissions so they may be
approved in a timely manner. Missing or insufficient information will delay approval.
COORDINATION: DDOT expects the submitter to coordinate with PSMA and TSA on
(a) the amount of public space needed for a project (b) ensuring coordination with
adjacent projects(c) special events appropriate detour routing, and (d) adequate level of
service for street operations.
REVIEW: TCPs shall be subject to review and verification by DDOT staff for
conformance to submission requirements.
• Traffic Control Plan (TCP) must be tailored to fit contractor’s specific situation.
• All traffic control shall conform to the standards set forth in 2003 Edition Manual
on Uniform Traffic Control Devices (MUTCD) and 2004 DDOT Work Area
Traffic Control Manual.
• All traffic control shall adhere to DDOT Standards Specifications for Highways
and Structures the (“red book”). Refer to Section 104.02 Maintenance of Traffic,
614.02 PCC Barrier and 616.01 – 616.23 Traffic Control.
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• Show all existing and proposed traffic control and parking signage.
• Waiver for cutting on suspended streets (streets that have been paved or
resurfaced within the last five years) must be approved by Public Space
Management Administration before applications are sent to Traffic Services
Administration/Work Zone and Public Safety.
• Provide temporary handicap ramps, crosswalks, and signs to meet Americans with
Disabilities Act (ADA) for all pedestrians within construction work zone area.
(NOTE: The entire handicap ramp including side flares must be located within a
crosswalk. The minimum crosswalk has a 15-foot width. The top and bottom of a
ramp must have a 5-foot clearance. Stop lines are located a minimum six feet
before a crosswalk. Stop lines are 12 inches wide. If using a striped crosswalk,
the stripes are two feet wide with 2-foot spacing and make stripes parallel to curb
line of street. Edge lines are required on all crosswalks.)
• Identify whether parking metered or residential permit parking (RPP) is restricted
or unrestricted.
• Cannot place equipment of any type in a NO PARKING ANYTIME ZONE, NO
STANDING OR PARKING ANYTIME, and NO STANDING OR PARKING
METRO BUS ZONE.
• All required dimensions shall be shown on crane and dumpster applications
• If any prohibiting signs (Regulatory) are proposed (No Left Turn and No Right
Turn, whether symbolic or text message), advance coordination with TSA must
occur to ensure that adequate traffic movements are provided in the vicinity of the
project site.
• Each plan page of all submissions must include the following statement, “I certify
that this plan conforms to the requirements set forth in the 2003 Edition Manual
on Uniform Traffic Control Devices (MUTCD), the 2004 DDOT Work Area
Traffic Control Manual and adheres to DDOT Standards Specifications for
Highways and Structures,” followed by an original signature. This requirement is
exempted for submission with Professional Engineer stamp.
TYPICAL TCPs FOR UTILITY WORK: 21 typical TCPs for utility work only are
available through the DDOT website in PDF format for use.
• When submitting DDOT typicals, make sure to specify street geometry, existing
street dimensions, street names, etc. Each typical Traffic Control Plan drawing
should contain the list of locations for which the TCP is applicable.
• Submit only those typicals that apply. The submitted typical TCPs should match
real street conditions. Otherwise, submit MOT/ TCP individually by actual real
street conditions and work zone location.
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INSPECTION: DDOT reserves the right to periodically inspect work zones to ensure
compliance, that safety measures are in place, and that the measures conform to the
approved TCP and criteria listed on the Traffic Control Plan Inspection Criteria
document.
Our goal is a safe work zone, thank you for your cooperation!
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This document provides a clear set of guidelines for the submission and approval of third
party certified Traffic Control Plans (TCP).
Otherwise, TCPs submitted with permit applications will be reviewed using the process
prior to the availability of this third party certified option.
Cranes that are used for short-term work (one to two days for life threatening situations
such as hoisting an AC and heating units, large medical equipment, etc.) are allowed to
be hand carried to the Associate Director’s Office at Traffic Services Administration for
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login without first going to Public Space Administration because of the short turn-around
of the work to be performed. Then the applicant can proceed to Public Space
Administration to purchase permit(s). Also, this type of work does not need ANC
notification.
No regulatory signs can be removed from the streets, and no traffic operation can be
changed in the District of Columbia without DDOT’s prior approval or authorization.
REVIEW: TCPs shall be subject to later review and verification by DDOT staff for
conformance to submission requirements. This places a level of professional expectation
on the submitter to certify that the TCP meets DDOT requirements.
Should the submitted TCP not conform to the submission requirements, DDOT reserves
the following options:
The following steps will be taken if a submitter does not comply with the submission
requirements:
The following steps will be taken if a submitter does not comply with the submission
requirements:
• Traffic Control Plan (TCP) must be tailored to fit contractor’s specific situation.
• All traffic control shall conform to the standards set forth in 2003 Edition Manual
on Uniform Traffic Control Devices (MUTCD) and 2004 DDOT Work Area
Traffic Control Manual.
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• All traffic control shall adhere to DDOT Standards Specifications for Highways
and Structures (the “red book”). Refer to Section 104.02 Maintenance of Traffic,
614.02 PCC Barrier and 616.01 - 616.23 Traffic Control.
• Provide Address of Premise for which Public Space Work is proposed.
• Provide Lot(s) and Square(s) number.
• Specify the MUTCD sign number, and size of all temporary signs utilized on the
MOT/TCP drawings.
• Specify North.
• Specify Names of all adjacent streets to Work Zone.
• Specify scope and sequence of work in narrative.
• Specify location and length of work zone (Advanced Warning Area, Transition
Area, Buffer Area, Active Work Zone, and Termination Area).
• Specify duration of work.
• Specify schedule of work hours.
• Specify limits of work.
• Show advance warning area, and location of the advance warning signs. The signs
shall be located at proper intervals to inform motorists of what to expect.
• Specify direction of travel, number of lanes, lane widths, and posted speed limit.
• Provide all adjacent intersections of the street under construction or under utility
work (independent of the area of the street under construction).
• Specify street geometry, median, curb and gutter lines, existing street dimensions,
and orientations; existing location and width of right-of-way for the street under
construction or utility work and its intersecting streets.
• Specify if parking is to be restricted and if bus zone will need to be relocated.
• Specify placement of all devices (Arrow board panels, signs, cones, drums,
attenuators, barricades, etc.).
• Specify spacing of devices (Arrow board panels, signs, cones, drums, barricades,
etc.)
• Specify taper and tangent lengths.
• Specify if turning radius will impact bus and trash truck turns.
• Orient traffic sign and device symbols with directions of traffic.
• Show work vehicle locations.
• Notes are encouraged.
• Show Key and/or Legend.
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TYPICAL TCPs FOR UTILITY WORK: 22 typical TCPs for utility work only are
available through the DDOT website in PDF format for use.
When submitting DDOT typicals, make sure to specify street geometry, existing
street dimensions, street names, etc. Each typical Traffic Control Plan drawing should
contain the list of locations for which the TCP is applicable.
Submit only those typicals that apply. The submitted typical TCPs should match
real street conditions. Otherwise, submit MOT/ TCP individually by actual real street
conditions and work zone location.
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INSPECTION: DDOT reserves the right to periodically inspect work zones to ensure
compliance, ascertain that safety measures are in place, and that the measures conform to
the approved TCP and criteria listed on the Traffic Control Plan Inspection Criteria
document.
Our goal is a safe work zone, thank you for your cooperation!
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APPENDIX C
TYPICAL WORK ZONE AND CRANE SET UP PHOTOS
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APPENDIX D
MPD Command center (24/7 line for reporting suspicious activities) 202-727-9099
Note that these numbers have been provided for convenience only. The contractor has the
ultimate responsibility of contacing the agency.
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Works Cited
i
U.S. Department of Transportation. Federal Highway Administration (FHWA) Manual on Uniform
Traffic Control Devices: 2003 Edition. November 2004. Washington D.C.:n.p
ii
U.S. Department of Transportation. Federal Highway Administration (FHWA). Final Rule on Work Zone
Safety and Mobility Brochure: Federal Register (69 FR 54562) .September 2004. Washington D.C
iii
American Association of State and Highway Transportation Officials (AASHTO), Roadside Design
Guide:3 rd Edition. March 2002. Washington D.C
iv
U.S. Department of Transportation. Federal Highway Administration (FHWA) Standard Highway Signs:
2004 Edition. Washington D.C.:n.p
v
American Traffic Safety Services Association (ATSSA), Quality Standards for Work Zone Traffic
Control Devices Brochure: 1992:n.p.
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
D.C. TEMPORARY TRAFFIC CONTROL MANUAL July 2006
NOTES
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