Ce 521 - Water Resources Engineering: University of Eastern Philippines
Ce 521 - Water Resources Engineering: University of Eastern Philippines
Ce 521 - Water Resources Engineering: University of Eastern Philippines
CE 521 - WATER
RESOURCES
ENGINEERING
SUBMITTED BY:
BALANQUIT, ABEGGEL I.
ESPINA, NICOLAS A.
GALIT, MAE ANN M.
SUBMITTED TO:
ENGR. MELCHOR O. ORONOS, JR
PART-TIME LECTURER
TOPIC:
The following data is essential for building up a decent hydraulic model of the Water
Distribution Network:
Elevation Data:
The elevation of a geographic location is
its height above or below a fixed reference point
Ground Elevations are typically used for the remaining model nodes. These
elevations are not required for calculating hydraulic grade line but are necessary for
determining available delivery pressures in the water system.
Demand Data:
Water demand is the measure of the total amount
of water used by the customers within the water system.
There are several things that can influence the amount of
water demanded of your system. One of the most
important jobs of a water system is to continually meet
this demand without interruption, rain or shine.
The per capita demands when multiplied with the
population of the area will result the total water demand.
Layout of the Area:
Storage Tank:
Pump:
Pipe Catalog:
Elevation Data:
The ground elevations can be collected using Total station or other means of
surveying. Today most of the land developers provide RELs (Road Edge Levels) as they
modify the natural terrain and flatten it to make it more suitable for constructing roads, storm
networks, etc.
Demand Data:
Customer Information Systems. A CIS typically tracks the following information about
each customer:
Account number
Name
Address (billing & service)
Meter-read consumption volumes
Average water usage
Date period for each meter reading
Meter information (make, size, etc.)
Classifications (customer/demand classes)
Core pieces of data useful to a modeller are usually available in the billing system. These
core pieces of information are as follows:
Location (service address) for each customer
Water usage for each customer (for demand analysis)
Classification of each customer (for demand analysis)
Utilities metering customer consumption have an excellent source of data for allocating
water demands.
Most billing systems contain information on monthly or bimonthly water consumption,
water use category, meter route number, and customer address. Some billing systems
contain additional information, such as number of residences for multifamily account or
business type for a commercial account. It is possible to extract this information into a
database software package, allowing for the use of automatic techniques to assign demands
to nodes.
Layout of the Area:
Topography sheets, CAD plans, Aerial photographs (even Google Earth Images),
give a better understanding of the topology of Roads, location of Schools, commercial
complexes, residential building, etc.
This information also helps the modeller/planner to understand and fix the location of
water treatment plants, pump stations, elevated storage reservoirs, etc. The use of GIS is
highly recommended by many leading practitioners as GIS has many merits as compared to
CAD.
Storage Tank:
In designing distribution system, the designer must know what kind of storage tanks
to be used. It could be available in a local market or through looking up the internet. Some
websites offer wide range of preferences that could befit for water distribution system.
Pump:
Commercially available pump types, the manufacturer’s brochures help the designer
get an idea about while modelling the network and decide the appropriate type of pump.
Pipe Catalog:
The pipes commercially available in the local market plays an important role in
deciding which pipes are economically affordable and readily available for design
consideration.
Elevation Data:
Demand Data:
There are three major steps that must take place in order to have properly allocated
demands in the model. These steps are:
1. Determine demands
2. Allocate demands in the model, and
3. Adjust demands to develop factors to convert from average day demands to the
demands conditions that are to be modelled.
The modeller will need to evaluate the modelling requirements, budget, and available
data in order to select the most appropriate demand calculation and allocation method.
Advances in the software and in GIS technologies allow assignment of demands
directly to the applicable pipe, at an appropriate distance the pipe.
Layout of the Area:
Storage Tank:
Water storage tanks are generally either pressure tanks or atmospheric tanks. Point-
of-use applications, like reverse osmosis storage tanks, usually implement pressure tanks.
Outdoor applications or large scale municipal water storage operations usually use
atmospheric tanks.
Pressure tanks use compressed air to create water pressure within the tank. A
pressure tank is constructed with an air chamber or bladder and comes with a pressure pre-
charge. As the tank fills up with water, the weight of the water will begin to compress the air.
As the air continues to compress, the pressure within the tank builds. When the tank reaches
a certain internal pressure, it signals to the feed source to cease delivery.
Atmospheric tanks do not contain air bladders or diaphragms to pressurize the water
within their reservoirs. Instead, atmospheric tanks hold water at ambient pressure. Ambient
pressure is simply the pre-existing pressure corresponding with wherever the tank is located
(usually about 0.5psi). There is no pressure exerted on the water within the tank.
To draw water out of an atmospheric storage tank, you will need a water booster
pump to move the water out of the tank and throughout the house. Since the water in these
tanks does not have any pressure exerted upon it, you will need the assistance of a pump or
gravity to move water out of the tank and through your pipes. They can also be used for
water distribution, transporting wastewater, or commercial chemical storage. Atmospheric
tanks tend to be much larger than pressure tanks, holding thousands of gallons at a time.
Pump:
Many kinds of pumps are used in distribution systems. Pumps that lift
surface water and move it to a nearby treatment plant are called low-lift pumps. These move
large volumes of water at relatively low discharge pressures. Pumps that discharge treated
water into arterial mains are called high-lift pumps. These operate under higher pressures.
Pumps that increase the pressure within the distribution system or raise water into an
elevated storage tank are called booster pumps. Well pumps lift water from underground and
discharge it directly into a distribution system. Most water distribution pumps are of
the centrifugal type, in which a rapidly rotating impeller adds energy to the water and raises
the pressure inside the pump casing. The flow rate through a centrifugal pump depends on
the pressure against which it operates. The higher the pressure, the lower the flow or
discharge. Another kind of pump is the positive-displacement type. This pump delivers a
fixed quantity of water with each cycle of a piston or rotor. The water is literally pushed or
displaced from the pump casing. The flow capacity of a positive-displacement pump is
unaffected by the pressure of the system in which it operates.
Pipe Catalog:
Sources:
https://www.linkedin.com/pulse/what-data-required-model-design-analyze-urban-water-
network-kulkarni
https://en.wikipedia.org/wiki/Elevation
David Chin, Water Resources Engineering, PEARSON, Singapore, 3rd Ed, 2013
https://en.wikipedia.org/wiki/Google_Earth
https://www.freshwatersystems.com/blogs/blog/what-is-a-water-storage-tank-and-how-does-
it-work
https://www.britannica.com/technology/water-supply-system/Pumps
https://books.google.com.ph/books?
id=p7_ba33B4owC&pg=PA21&lpg=PA21&dq=how+to+obtain+ground+elevations+fo
r+water+distribution&source=bl&ots=EgFteFl4vz&sig=ACfU3U1SEsMKKOdjss_rVjEt
-
QhzZqyjDQ&hl=en&sa=X&ved=2ahUKEwiC5uu6oqzpAhWIBIgKHeLHDqMQ6AEwC
3oECA0QAQ#v=onepage&q&f=false
http://www.waterhelp.org/index.php/article/2279