Chapter 14 Water Supply Flashcards
Name the two types of water supply systems in North America.
Public and Private
Name four components of a water supply system.
Water supply source. Processing and treatment facility. Means of moving water. Water distribution and storage systems.
How many times more saltier is the ocean then fresh water?
220 times
Name three methods of moving water.
Gravity, Pumping, Combination
How high does the water source need to be above the highest use point in a gravity system?
100’
Most direct pumping systems are found in what two areas?
Industrial and agricultural.
In a direct pumping system, what is necessary to ensure a reliable system?
Duplicate pumps and piping.
Many industrial facilities have their own elevated storage tanks making this kind of system possible.
Combination system.
Name the four system components of a water distribution system.
Piping. Storage tanks. Isolation and control valves. Hydrants
Generally made of cast iron, ductile iron, asbestos cement, steel, PVC, plastic, or cement.
Underground water mains.
Name the three types of water mains found in a water distribution grid.
Primary Feeders. Secondary Feeders. Distrubutors
Also know as arterial mains. Range from 16” to 72”.
Primary Feeders
Interconnect with primary feeders to create a grid. 12” - 14” wide. Control Valves are used to isolate each of these.
Secondary Feeders
6” - 8” wide. Serve individual fire hydrants.
Distributors
T or F To ensure a sufficient water supply, two or more primary feeders should run from the source of supply to the high risk and industrial districts of the community along separate routes. Similarly, secondary feeders should provide water from the primary feeders along two directions to any end point.
True
Today, …..inch pipe is often the minimum size used, although some communities are allowing ……inch pipes in residential subdivisions.
8”, 6”
Elevated water storage tanks are usually constructed of what?
Concrete or steel.
What is the range of capacity for a elevated storage tank?
5000 to over a million gallons.
Most valves are constructed of what?
Brass, steel, or cast iron.
Name the two types of valves used in a water supply system.
Isolation and control valves.
Either gate valves or butterfly valves. Maximum length of valve spacing should be 500’ in high value districts and 800’ in other areas. Should be tested (opened and closed) at least once a year. Non-indicating type valves on municipal water supply systems. Private systems usually have indicating valves. Typically found on secondary feeders.
Isolation valves
Name the two most common indicating valves.
OS&Y and Post Indicator Valve (PIV)
What position is the OS&Y vale is you can see the stem?
Open
Name seven types of control valves.
Pressure reducing. Pressure sustaining. Pressure relief. Flow control. Throttling. Float. Check.
Located between public and private water supply systems.
Control Valves.
Two additional components that are installed between a public and private water supply system besides control valves.
Flow Meter. Back Flow Preventer
Fire hydrants are usually connect to the water system by what size pipe?
6”
Fire hydrants should not be spaced more then ……. in high value districts. Hydrants should be located at ………intersection. Additional hydrants may be needed where distances between intersections exceeds 350 to 400 feet.
300’, every other. (this place a hydrant within one block of a building).
Fire hydrant located on a dead end main that receives water from only one direction.
Dead End Hydrant
Fire hydrant that is located on a secondary feeder or distributor main that receives water from two directions.
Circulating Hydrant
Fire hydrant that receives water from two or more directions.
Circulating feed
Water Main arranged in a complete circuit so that water will be supplied to a given point from more then one direction.
Loop system
Can provide a constant volume of water at a constant pressure.
Fire Hydrants
Fire hydrant bonnets, barrels, and foot pieces are made of what? Internal workings are made of what? Valve facings are made of what?
Cast iron. Bronze. Rubber, leather, or composite material.
Name the two main types of fire hydrants used in North America.
Dry-barrel and Wet-Barrel
Hydrant discharges consist of what?”
One 4 - 4/12” outlet. (Pumper outlet nozzle, Steamer connection) Two 2 1/2” outlets.
Hydrant specs require a ……. valve opening for standard three way hydrants and a ……connection to the water main.
5”, 6”
Standard on Fire Hose Connections
NFPA 1963
Hydrant colors vary by what?
Jurisdiction
Recommended Practice for Fire Flow Testing and Marking of Hydrants
NFPA 291
Factors that affect hydrant flow rate. SLIP
S= size of main. L=length of the main. I=Internal condition of the main. P= Pressure within the main.
Class AA. 1500 gpm or greater. 20 psi.
Light Blue
Class A. 1000-1499 gpm. 20psi.
Green
Class B. 500-999 gpm. 20 psi.
Orange
Class C. 500 gpm or less. 20 psi.
Red
Hydrants must be inspected and operated how many times a year?
Two
When a dry barrel stem nut is turned to open the hydrant it is pushing the valve what way?
Down
Dry Barrel hydrants should be completely open or completely closed to prevent what?
Undermining
List some sources of alternate water supply’s.
Adjacent private water systems. Lakes,ponds, rivers, and the ocean. Swimming Pools. Farm stock tanks. Rainwater collection cisterns and detention ponds.T
T of F. Almost any static water source can be used as a alternate water source if it is sufficient in quantity and not contaminated to the point of creating a health hazard or damaging the fire pump.
True
How many inches should be above and below a intake strainer?
24”
How shallow of water can a floating strainer draft from?
24”
Drafting hydrants are usually constructed of what? How many gpm do they supply as a minimum?
Steel or PVC. 1000gpm
Areas that lack a public water supply system or that have inadequate volume and pressure, frequently have to use what to get water for firefighting?
Rural water supply operations. (Water shuttle, Relay Pumping)
Standard on Water Supplies for Suburban and Rural Fire Fighting.
NFPA 1142
Water shuttle operations are recommended in what two case?
Supply is greater then 1/2 mile away. Distance exceeds the available supply hose.
Should mobile water supply apparatus drivers remain in their vehicle during filling and dumping?
Yes
What are the three components to a water shuttle operation?
Dump site at the fire. Fill site at the water source. Mobile water supply apparatus to haul water from fill site to dump site.
Portable tanks have capacity beginning at what?
1000 gallons.
Name two types of portable water tanks.
Square with a frame. Round frame less.
Multiple portable water tanks can be interconnected in what two ways?
Through their drain valves. Through a jet siphon.
How do you calculate the volume of water being supplied in a water shuttle operation?
Total gallons carried divided by the total time (fill time, travel time, dump time), this will give you a gpm.
Name the four methods a mobile water supply apparatus can unload.
Gravity dumping through 10-12” dump valves. Jet assist dump that increases flow rate. Apparatus mounted pumps that off load the water. A combination of these methods
Standard for Automotive Fire Apparatus.
NFPA 1901
NFPA requires that mobile water supply apparatus on level ground be capable of dumping or filling at a rate of what?
At least 1000 gpm (this rate requires adequate venting and and openings in tank baffles)
Both fill and dump sites should be arranged so that a minimum of what is required?
Backing or maneuvering of apparatus.
What two factors should be considered when setting up a relay pumping operation?
Is the water supply adequate for the duration of the incident? Can a relay be set up quick enough that it is worthwhile?
The number of pumpers and the distance between pumpers in a relay operation is determined by these 5 things.
Required volume of water. Distance between source and fire. Size of supply hose available. Amount of hose available. Pumper capacity.
In a relay pumping operation where should the pumper with the greatest pumping capacity be located?
At the water source.
Use of two or more pumpers to move water over a long distance by operating them in series.
Relay Pumping
What is the best way to prepare for a relay operation?
Plan them in advance and practice them often.
