Water Distribution Grades 1 & 2 Flashcards
Which agency legal limits on the concentration levels of harmful contaminants in potable water distributed to customers?
a. National Primary Drinking Water Regulations Agency
b. US Environmental Protection Agency
c. US Public Health Service
d. Occupational Health and Safety Administration
b. US Environmental Protection agency
The number of monthly distribution system bacteriological samples required is
a. based on the water withdrawal permit limit.
b. based on the system size.
c. based on the population served.
d. different for each state.
c. based on the population served.
What is the maximum contaminant level for total trihalomethanes (TTHMs) in the United States?
a. 0.040 mg/L
b. 0.060 mg/L
c. 0.080 mg/L
d. 0.100 mg/L
c. 0.080 mg/L
Under the Surface Water Treatment Rule, disinfection residuals must be collected at the same location in the distribution system as
a. coliform samples.
b. total trihalomethanes.
c. disinfection by-products.
d. alkalinity, conductivity, and pH for corrosion studies.
a. coliform residuals.
Iron can cause “red water” and thus customer complaints when its concentration is above its secondary maximum contaminant level of
a. 0.01 mg/L
b. 0.05 mg/L
c. 0.10 mg/L
d. 0.30 mg/L
d. 0.30 mg/L
The goal of the Surface Drinking Water Act is for each _____ to accept primary enforcement responsibility (primacy) for the operation of the state’s drinking water program.
a. state
b. water treatment plant
c. operator
d. municipality
a. state
What is the objective of the Total Coliform Rule?
a. To provide Cryptosporidium protection in new facilities
b. To ensure safe levels of lead and copper in drinking water
c. To protect the public from exposure to Giardia and Cryptosporidium
d. To promote routine surveillance of distribution system water quality to search for fecal matter and/or disease-causing bacteria
d. To promote routine surveillance of distribution system water quality to search for fecal matter and/or disease-causing bacteria
Which agency sets standards on the concentration levels of harmful contamination in drinking water?
US Environmental Protection Agency
What is the difference between the different Tiers of violations and which on is the most serious?
- Tier 1 is an acute MCL violation: requiring public notification within 24 hours - and is the Most Serious
- Tier 2 violations: require public notification within 30 days
- Tier 3 violations: require public notification within 1 year
A positive E. coli test must be reported to the primacy health agency within what time period?
24 hours
How is the required number of monthly bacteriological samples determined?
By the population served
What is the action level for lead in first-draw samples taken from customer taps?
0.015 mg/L or 15 ppb
What authority provides specific sampling instructions?
The state primacy agency (Department of Health)
According to the Lead and Copper Rule, what is the action level for lead?
0.015 mg/L (15 ppb)
A water system is designated a “community public water supply” if it serves how many homes?
15 or more homes
What is the formula for calculating Detention time in Hours?
Detention Time (hrs) = Total Volume (gal) x 24 hrs/day then divide by Daily Flow (gals/day)
What resource allows you to convert to units, such as feet to inches, simply by following the instructions in the table heading?
A conversion table
How many gallons are in a cubic foot?
7.48 gallons in a cubic foot
If the water level rises by 15 feet, how many wards has it risen?
5 yards
What is the formula for Average Daily Flow?
Sum of All daily flows divided by Total number of daily flows used
How do you convert deciliters to milliliters?
Multiply by 100 or Move the decimal TWO places to the RIGHT
Head pressure is measured in
a. absolute pressure.
b. gauge pressure.
c. feet.
d. foot-pounds
c. feet
A plat is
a. a map.
b. a corrosion point on a map.
c. an organelle found in some protozoans.
d. a highly corrosive soil type.
a. a map.
At which time of the day of water stored in the distribution system the oldest?
a. Early morning
b. Late morning
c. Early afternoon
d. Late evening
a. Early morning
Water mains should primarily be sized based on
a. earthquake size potential.
b. peak domestic and commercial demands.
c. peak commercial and industrial demands.
d. adequate fire flow at an appropriate pressure.
d. adequate fire flow at an adequate pressure.
The most desirable residential pressure ranges from
a. 20 to 35 psi
b. 35 to 50 psi
c. 50 to 75 psi
d. 75 to 90 psi
c. 50 to 75 psi
Domestic water use includes water that is supplied to residential areas, _____, and institutional facilities.
a. public parks
b. commercial districts
c. industrial facilities
d. municipal buildings
b. commercial districts
The Riparian Doctrine is sometimes called the “Rule of
a. first come, first serve.”
b. reasonable sharing.”
c. equal use.”
d. eminent domain.”
b. reasonable sharing.”
During which season is water use typically the highest?
Summer
Of the common types of distribution systems, which is considered the LEAST desirable?
Tree system
What type of valves should be provided so that areas within the system can be isolated for repair or maintenance?
Shutoff Valves
Head is measured in
a. absolute pressure.
b. gauge pressure.
c. feet.
d. foot-pounds.
c. feet.
If the pressure head on a fire hydrant is 134 ft, what is the pressure in psi?
a. 50 psi
b. 52 psi
c. 54 psi
d. 58 psi
d. 58 psi
- 134 ft divided by 2.31 ft/psi = 58 psi
The velocity of water is calculated as the quantity of water that flows through the pipe
a. divided by the cross-sectional area of the pipe.
b. divided by the time the water takes to reach its destination.
c. divided by the water’s weight in cubic feet.
d. multiplied by resistance to flow.
a. divided by the cross-sectional area of the pipe.
What is the term for water pressure in a main or in a container that is measured by a gauge?
Gauge Pressure
In hydraulics, how is head expressed?
Foot Pounds per Pound (ft-lb/lb)
What is the term for pressure measured in terms of height of water (in meters or feet)?
Head
What are the THREE types of head pressure?
- Elevation head
- Velocity head
- Pressure head
The highest degree of protection for the exterior of a coated steel pipe is
a. cathodic protection.
b. bituminous materials.
c. plastic coatings.
d. polyethylene tapes.
a. cathodic protection.
The C value is a measure of a pipe wall’s
a. smoothness.
b. smoothness, which allows for even flow.
c. smoothness, which retards turbulent flow.
d. roughness, which retards flow due to friction.
d. roughness, which retards flow due to friction.
Which of the following is a type of joint for ductile iron pipe?
a. Expansion joint
b. Push-on joint
c. Bell and spigot with rubber O-ring
d. Rubber gasket joint
b. Push-on joint
What is the term for a sudden repeated increase and decrease in pressure that continues until dissipated by friction losses?
a. Pipe knocking
b. Water hammer
c. Pipe shear
d. Beam breakage
b. Water hammer
Which of the following is NOT a type of joint that generally used today for connecting DIP (ductile iron pipe) and fittings?
a. Push-on joint
b. Flanged joint
c. Riveted joint
c. Riveted joint
What term refers to the process by which organic compounds pass through plastic pipe?
Permeation
What measurement of a pipe’s strength refers to its ability to withstand the pressure exerted on it after it has been buried in a trench?
External load
What type of cylinder pipe is manufactured by casting mild steel reinforcing cages and a steel cylinder with welded joint rings within a thick concrete core?
Reinforced concrete cylinder pipe
When PVC pipe is stacked loose, it should not be stacked more than how high?
a. 2.0 feet
b. 3.0 feet
c. 5.0 feet
d. 7.5 feet
b. 3.0 feet
What is the most common cause for pipe joint failure (leaking) in newly laid pipe?
a. The use of a cracked gasket
b. Not pushing the spigot end the full distance into the bell
c. Not having the joint completely clean
d. An incorrect trench bedding angle
c. Not having the joint completely clean
The backfill material for a pipe installation should contain enough _____ to allow for thorough compaction.
a. moisture
b. sand
c. gravel
d. mixed sizes
a. moisture
What is the appropriate angle of repose for average soils when using the sloping method for the prevention of cave-ins? (Note: horizontal to vertical distance, respectively)
a. 0.5 : 1.0
b. 1.0 : 1.0
c. 1.5 : 1.0
d. 2.0 : 1.0
b. 1.0 : 1.0
Which of the following statements is true regarding unloading gaskets?
a. Always have gaskets as near the trench as possible for easy installation
b. Always store gaskets in a clean, secure location until they are needed
c. Store gaskets near electric motors or other operating electrical equipment
d. Don’t worry about getting gaskets dirty while unloading, as long as they are cleaned before installation
b. Always store gaskets in a clean, secure location until they are needed
Wherever a water main crosses a sewer line, the water main should be at least _____ above or below the sewer line.
a. 12-inches
b. 18-inches
c. 24-inches
d. 30-inches
b. 18-inches
What form of pipe shipment is preferrable from the user’s standpoint because the pipe can usually be unloaded directly at the jobsite?
Truck Delivery
What is the greatest expense relating to pipe installation?
Excavation
What is the term for the process of installing tightly spaced upright planks against each other to form a solid barrier against faces of the excavation?
Sheeting
If an excavation on a road requires that one of the lanes be closed and the speed limit is 25 mph (40 kph), how many cones are required to divert the traffic?
a. 6
b. 9
c. 13
d. 15
a. 6
Which of the following is NOT generally a process used for compacting the pipe embedment and backfill placed in a trench?
a. Tamping
b. Vibrating
c. Saturating with water
d. Sifting
d. Sifting
Leakage is defined as the volume of water that must be added to the full pipeline to maintain a specific test pressure within a _____ range.
a. 10 psi
b. 5 psi
c. 3 psi
4. 12 psi
b. 5 psi
Which of the following is NOT one of the commonly used methods of applying a disinfectant to piping?
a. Stream method
b. Slug method
c. Tablet method
d. Continuous feed method
a. Stream method
Under any soil conditions, cave-in prevention is required for trenches or excavations _____ deep or more.
a. 15 feet (4.6 m)
b. 10 feet (3.0 m)
c. 5 feet (1.5 m)
d. 2 ft (0.6 m)
c. 5 feet (1.5 m)
When disinfecting a new pipeline with calcium hypochlorite tablets or granules, what should the chlorine target be?
25 mg/L
How deep should the compacted covering layer be for pipe less than 8-inches in diameter and for pipe larger than 8-inches in diameter?
- 8-inches or less = 6 - 12 inches
- 8-inches or more = 12 - 24 inches
How much leakage is allowed for a mew pipeline test?
The amount is given in the AWWA Standards and manuals.
How must a pipeline be prepared before a sample is taken for bacteriological testing?
The pipeline must be flushed of chlorinated water and refilled with water from the system.
What term refers to the process of repeatedly pushing in pressurized water pipe vertically near the bottom of the loose fill at intervals along the excavation?
Jetting
A corporation stop is used for a
a. Service line.
b. Pump discharge line.
c. Tank inlet.
d. Tank outlet.
a. Service line.
Compression fittings used with copper or plastic tubing seal by means of
a. a beveled sleeve.
b. a compression ring.
c. a compressed beveled gasket.
d. compressed O-rings located at either end of the fitting’s beveled neck.
c. a compressed beveled gasket.
Water meter pits are usually used in
a. areas where flooding will most likely occur.
b. areas where flooding is very rare.
c. cold climates.
d. hot climates.
c. cold climates.
Which of the following is NOT an advantage of installing meters outside in boxes?
a. In areas where ground frost is nominal, a meter box can be relatively small, inexpensive, and easy to install
b. If the boxes can always be readily located, meter boxes can make meter reading easier because meter readers do not have to enter the building
c. In areas where there is deep frost, meter pits are much more expensive to construct
d. Placing meters outside eliminates the need to enter buildings to replace the meters, which is difficult in some inside locations
c. In areas with deep frost, meter pits are much more expensive to construct
Other utilities will allow installation of a meter in a crawl space or utility closet as long as (1) the meter can be easily accessed by a meter reader or (2)
a. the meter is equipped with a remote reading device.
b. the homeowner can easily access and report the meter readings.
c. the meter can self-report to the utility.
d. water fees in the area are fixed and readings are unnecessary.
a. the meter is equipped with a remote reading device.
What may cause galvanized iron pipe to corrode excessively?
Direct connection to brass and other dissimilar metal fittings
What is a curb stop used for?
Turning off a customer’s service for repair or as the result of nonpayment
What is the typical service line size for a single-family residence?
3/4 inch
What is the term for the valve used to connect a small-diameter service line to a water main?
Corportation Stop
What is generally considered to be the best location for a tap on a main?
At an angle of about 45 degrees down from the top of the pipe
Which type of valve should be installed at a dead-end water main?
a. Vacuum valve
b. Air valve
c. Blowoff valve
d. Pressure-relief valve
c. Blowoff valve
Which type of valve operates similar to a diaphragm valve?
a. Vacuum relief valve
b. Globe valve
c. Pressure-relief valve
d. Butterfly valve
b. Globe valve
Which type of valve can go from fully open to fully closed with a quarter turn?
a. Plug valve
b. Needle valve
c. Globe valve
d. Pinch valve
a. Plug valve
Foot valves are a special type of
a. relief valve.
b. control valve.
c. check valve.
d. plug valve.
c. check valve.
Which type of valve would be best to use to precisely throttle flow?
a. Globe valve
b. Butterfly valve
c. Rotary valve.
d. Needle valve.
d. Needle valve.
Which type of valve is used to isolate a pump on the suction side?
a. Butterfly valve
b. Globe valve
c. Gate valve
d. Ball valve
c. Gate valve
When fully opened, which type of valve will have the highest head loss?
a. Gate valve
b. Plug valve
c. Globe valve
d. Ball valve
c. Globe valve
Which type of valve will prevent the collapse of a pipe?
a. Pressure-relief valve
b. Needle valve
c. Pinch valve
d. Air-and-vacuum relief valve
d. Air-and-vacuum relief valve
List some valves used in water systems:
- Gate valve
- Globe valve
- Pressure-relief valve
- Air-and-vacuum relief valve
- Diaphragm valve
- Pinch valve
- Rotary valve
- Butterfly valve
- Check valve
What type of valve is installed at frequent intervals in the distribution piping so that small sections of water main may be shut off for maintenance or repair?
Isolation valve
What are the two principal types of throttling valves used in a water system?
- Pressure-reducing valves
- Altitude valves