Specifications For Underground Water Storage Tanks For Fire Protection
Specifications For Underground Water Storage Tanks For Fire Protection
Specifications For Underground Water Storage Tanks For Fire Protection
Introduction
1.1. Scope
The construction of underground tanks for fire protection in accordance with Carroll
County Code, Chapter 112, Fire Protection, is part of a program designed to improve
the level of protection from fires in residential and commercial properties. These
Specifications, along with associated documents, provides the information necessary
for the construction and placement of fire protection tanks used for this purpose.
1.2. Purpose
The purpose of this specification is to provide the technical information required for the
construction of underground water storage tanks in accordance with Ordinance No. 0412 and The Code of Public Local Laws and Ordinances of Carroll County Maryland,
Chapter 112, Fire Protection.
2.
Underground tanks
2.1. Materials for a static water supply tank
2.1.1.
2.1.2.
2.2. Features
2.2.1.
The tank system shall include a device for holding the tank in position against
floatation (deadman). This configuration shall be part of the tank package and
approved by the tank manufacturer. Installation shall be in accordance with the
manufacturer's recommendations.
2.2.2.
The tank shall include a removable access cover at grade (manhole) to allow
entry for maintenance and inspection of the inside of the tank. An internal
ladder shall be securely mounted to the tank. The cover shall be properly
secured and locked.
2.2.3.
A pad consisting of 4 inch thick concrete shall be placed over the tank, and
shall encompass all fittings. Refer to tank drawings for concrete specifications.
2.2.4.
Fittings
2.2.4.1.
2.2.4.2.
2.2.4.3.
2.2.5.
2.2.6.
The standard tank drawing 03-02, Tank, Fire Suppression Water Storage,
30,000 Gallon (Appendix 5.2) defines the requirements for a typical 30,000
gallon, 10-foot diameter tank installation. Tank sizes other than 30,000 gallons
may require additional drawings to be provided to fit the requirements for a
particular site. Drawing 06-02, Tank, Fire Suppression Water Storage, 12,000
Gallon defines the general requirements for construction of 8-foot diameter
tanks, and shall be used accordingly. Supplemental drawings shall be reviewed
and approved by the Fire Official prior to construction on an as needed basis.
2.3. Installation
2.3.1.
Location and orientation of the tank shall be determined during site plan or
preliminary subdivision plan layout, as approved by the Fire Official.
2.3.2.
2.3.3.
2.3.3.1.
The draft connection shall be located 8 feet or less from the edge of the
parking surface or curb line. This allows for one 10 foot section of suction
sleeve to be used for drafting. The draft connection opening shall be
turned facing directly toward the road surface.
2.3.3.2.
Total elevation from the bottom of the suction pipe to the centerline of the
draft connection shall not exceed 15 feet zero inches. This dimension shall
be minimized as much as possible to reduce head loss, while maintaining
correct depth of cover over tank, per manufacturers specifications.
2.3.3.3.
2.3.3.4.
2.3.4.
The tank shall be operable with a rate of flow (fire flow) of 1000 gallons per
minute (GPM) minimum using a fire department pumper operating under
normal conditions.
2.4.2.
2.4.3.
A pressure test shall be performed after the tank is installed and covered at a
maximum pressure of 5 psi (pounds per square inch) and held for a time period
as determined by the Fire Official, or per manufacturers specifications.
2.4.4.
2.4.5.
Final approval will be made per notification in writing by the Fire Official.
A pulloff shall be constructed per Appendix 5.1, Drawing 03-01, Pulloff, Tank
Access, unless otherwise specified. The requirements for each site will be
evaluated and approved by the Fire Official prior to start of work. Details shall
be indicated on the site or subdivision plan as applicable.
2.5.2.
No obstructions shall impede access to tank fittings. The facility shall remain
accessible on a year-round basis.
2.5.2.1.
2.5.2.2.
Snow shall be plowed from the access way as required to maintain access
at all times.
2.5.3.
2.5.4.
A reflective sign shall be posted which clearly indicates tank full capacity and
identification (ID) number. An identification number shall be assigned by the
county and posted at the site.
2.5.5.
2.5.6.
All fittings above grade shall be painted with exterior-grade enamel. Color
shall be yellow unless otherwise specified.
2.6. Inspections shall be performed by the Local Fire Department and documented as
appropriate according to the following schedule:
2.6.1.
Monthly inspections shall consist of a visual check to confirm that the water
level is full and to determine if any damage has occurred.
2.6.2.
2.6.3.
Annual inspections shall include all of the above, with the addition of an
operational test to be conducted by the local fire company.
2.6.4.
3.
Definitions: For applicable definitions, see Section 112-4 of the Carroll County Code.
4.
References
4.1. Published standards
4.1.1.
4.1.2.
NFPA 1142 - Standard for Water Supplies for Suburban and Rural Fire
Protection
4.1.3.
The Code of Public Local Laws and Ordinances of Carroll County Maryland,
Chapter 112.
4.2.2.
Underground Tanks & Dry Fire Hydrants Maintenance and Inspection, Chief
Greg Dods / Regional Fire Protection Committee, 2003.
5. Appendix
5.1. Drawing 03-01, Pulloff, Tank Access.
5.2. Drawing 03-02, Tank, Fire Suppression Water Storage, 30,000 Gallon.
5.3. Drawing 06-02, Tank, Fire Suppression Water Storage, 12,000 Gallon.
5.4. Maintenance and inspection procedures (item 4.2.2).