Water Distribution manager Flashcards
Tastes and odors in water are not as noticeable when the water is:
Cold
The continuous natural recycling of water is called?
Hydrologic cycle
The concentration of _______ ions in a water supply determines whether the water will act as an acid or a base.
Hydrogen
Calcium and/or magnesium compounds cause ________ in water.
Hardness
When the iron content is over 0.3 mg/L what problems could you expect?
Staining and taste
The weight of one cubic foot of water is:
62.4 lbs
One cubic foot of water contains:
7.48 gallons
Temporary cloudiness in a freshly drawn sample of tap water may be caused by:
Air
What chemical is added to coliform sample bottles to remove residual chlorine from the potable water being sampled?
Sodium thiosulfate
The pH scale is used to measure the concentration of:
Hydrogen ions
A particular electric motor is wound for 3-phase current. If one phase cuts out while It is in operation, the motor will:
Heat and be damaged unless it is stopped by a control device.
The term “air-gap separation” means:
A physical break between the water supply line and the receiving vessel.
Which of the following backflow prevention measures would normally be required on the feed water line connected directly to a low pressure boiler which utilized chemical-feed water treatment?
Reduced pressure principle device.
A covered roof tank holding domestic water for a building has a low inlet full line. This inlet requires:
No change or correction
Chlorine cylinders should be kept ________than the temperature of the chlorinator to prevent chlorine gas from condensing in the transfer line or in the feed operation.
Cooler
All of the following are types of starters for electrical motors except:
Across the line
Actuator
Reduced voltage
Capacitor
Actuator
The current rating of the time-lag fuse placed in an electrical circuit for a motor should be at least:
The same as that of the motor.
Which of the following should be used by an operator to test for residual chlorine?
DPD
A pitot tube is used to measure:
Velocity head
How often should a reduced pressure backflow prevention assembly be tested?
Once per year
As the temperature of the water increases, the disinfecting action of the chlorine is:
More effective
After chlorination, the free chlorine residual includes:
OCl- and HOCl
Hypochlorite and Hypochlorus acid
If a chlorinator is connected to the bottom valve of a half full one ton cylinder, the chlorinator is withdrawing:
Liquid
Top connection is gas, bottom is liquid
What type of rupture or breakage may occur when a pipe is unevenly supported along its length?
Beam breakage
What color does DPD produce when reacted with a water that contains residual chlorine?
Pink
What is the purpose of a hydrostatic test?
To measure leakage in a pipe section
To test the thrust restraints
To test the integrity of assembled valves and fittings
Cathodic protection of elevated steel water tanks is:
A protective deposit of metal molecules laid down on the inside of the tank through action of a small electric current.
Which of the following is the most likely to cause corrosion?
Pressure
Dissolved oxygen
Temperature
Velocity of flow
Dissolved oxygen
When found in a water supply, which of the following conditions tend to increase the corrosiveness of the water on metals?
High alkalinity
High dissolved carbon dioxide
High pH
Low dissolved oxygen content
High dissolved carbon dioxide
What type of meter would be the most appropriate for a manufacturing plant needing a steady flow of 200 gal/min?
3” turbine meter
Disease producing microorganisms are commonly called:
Pathogens
How will water demand be affected when a utility charges users based on consumption?
Lower per capita use than flat-rate water systems
A chlorine taste is reported by two or more customers in a given section of town some distance from the plant. If you are required to handle all complaints and you receive this complaint, how should it be handled?
Inform the plant that a chlorine-taste problem exists and that they need to add more chlorine.
What should a supervisor do if an employee is performing work in an unsafe manner?
Stop the work immediately and train the employee to perform the work safely
What would not be considered and acceptable standby arrangement for times of power outage at the pumping station?
Another large pump and motor ready to put into place.
Regulations promulgated under the “Safe Water Drinking Act” require utilities do all the the following except:
To maintain records of water quality tests, and establishes maximum contaminate levels for chemical, physical and bacteriological contaminants.
requires public notification in the event of a violation of a water quality standard.
Requires routine chemical and bacteriological testing.
Requires the utility to have a source of water from wells
Requires the utility to have a source of water from wells
When obtaining a pipeline right-of-way, which factor does NOT need to be considered.
Access for repai and replacement Areas of unstable earth Ease of installation Restoration costs following installation and repair Velocity in pipeline
Velocity in pipeline
If an underground utility map shows at Station 180+20 there is a valve, and at Station 220+10 there is another valve, the distance between the valves would be:
3,990 ft.
At the time that new service connections are made, detailed records should be kept to allow future location with minimum effort. These maps should include:
Applicants name and address
Date of installing
Detailed measurements and depths
Size and kind of materials used
What is the secondary MCL for chloride?
250 mg/L
Which of the following is the most effective disinfectant compound?
Dichloramine
Hypochlorus Acid
Monochloramine
Nitrogen Trichloride
Hypochlorous Acid
Scale in a pipeline is caused by:
Insoluble carbonate compounds
The type of corrosion caused by the use of dissimilar metals in water systems is known as:
Galvanic corrosion
How many amperes of electricity (110-115 volts) will it take to injure or kill a person?
1/3 amperes
If the horizontal scale on a plan is 1” = 100’ and the vertical scale is 1” =10’ , how long a line would represent a level length of pipeline 175’ long?
1.75”
Hydrants in the distribution system should be:
Placed according to the fire flow requirements for a given area
What type of valve should be installed between fire hydrants and mains?
Auxiliary valves
In any locality the amount of water that a water bearing formation will yield depends on the:
Thickness and permeability of the formation
Static head is the:
Pressure due to the depth or elevation of water
If any foreign material such as sand, gravel, and tar is present when a joint is made up, it is likely the joint will:
Leak
A master meter on the water supply source is required to:
Comply with water right requirements
Determine unaccounted for water
Determine chemical dosages
Rate of flow from a large pumping station could be measured by:
Turbine meter and Venturi meter
The type of meter to be used in any given installation should be determined by the:
Amount of sand scale or other foreign matter that may be present in the water supply.
Range of flow rates, plus allowable pressure loss
Type of service (domestic, commercial, or irrigation etc)
Measuring the flow of water can be done by a weir, pitot tube, orifice, and by what method?
Volume measurement for a given period of time
Which of the following service line materials is not flexible?
Lead
Copper
High Density Polyethylene
Galvanized iron
Galvanized Iron
The theoretical possible suction list of a pump at sea level (14.7 atmospheric pressure) capable of pulling a complete vacuum is:
34 ft. of water
A characteristic of the plunger or piston-type pump is that within the limits of design…
A fixed rate of flow can be continuously delivered against a variable head.
What information is required on the tag during a switch lock-out?
Name of person who locked out the switch.
Which would not be acceptable as a coating inside a water storage tank?
Alkyd enamel
The main purpose of a distribution system reservoir is to:
Provide storage to meet peak demands
In instances where potentially non-potable water is connected directly with a potable water system, one method of eliminating such a cross connection is:
Providing an air gap between the two systems
Calculate the brake horsepower necessary to pump 650gpm against a head of 80ft if the efficiency is 80%
16.5 hp
BHP formula
Which machine can be used to make an 8 inch fire line connection on a 12 inch cast iron, or ductile iron water main under pressure?
Tapping machine
When a fire hydrant is operated, it should be:
Opened fully
Which of the following would least likely be used to determine if a residential service meter is working properly?
Check for reasonable consistency of monthly bills
Draw a measured amount in a barrel
Measure with a series meter
Pull out and check meter
Put a calibrated listening device in the meter as it runs
Put a calibrated listening device in the meter as it runs
As a positive displacement water meter becomes worn with use, it tends to:
Under register
Which method could be used to determine the location of a leak in a water main?
A geophone
Electrical continuity is assured during installation of iron water mains by use of:
Electrical wire (jumper)
Pressure in distribution lines should not be allowed to drop to zero unless absolutely necessary because:
Contaminated water may seep into the lines
Which ductile iron pipe joint would be the most appropriate for an above ground installation where rigidly is important?
Flanged joint
A situation where the supervisor encourages employees to make their own decisions in specified areas is considered to be:
Highly desirable, since it encourages employee growth and free’s the supervisor for other tasks.
Job specifications refer to:
The principal duties and functions of various jobs, including the scope and kinds of authority related to these jobs.
The MOST important thing a supervisor can do regarding potential personnel problems is to:
Write each incidence down, file it for reference and talk to the personnel involved.
Where must the task of building a public relations attitude start?
With top management
The major reason why the person in charge of a public relations program should be a member of upper management is:
The ability to influence policy
The major purpose of an inventory of actual physical units is to:
Check of significant differences in inventory records
A uniform rate schedule:
Charges the same price for each gallon of water consumed, regardless of wether the consumption is large or small.
According to the safe water drinking act regulations, where should routine chlorine residual monitoring occur?
Entrance to the distribution system and the distribution system
Which of the following would NOT be included under “cost of injuries” ?
Loss of future earning power
New equipment installed
Spoiled work
Time lost by supervisor
New equipment installed
In order to budget a certain number of personnel, a water distribution operator should know the amount of “backlog” work, the rate in which it increases, and how to apply ___________ to determine total estimated man hours:
Job standards
What is the chemical symbol for sodium?
Na
The chemical formula for water is:
H2O
Specific conductance provides an estimate of:
Total dissolved solids
The difference between the hydraulic energy line and the hydraulic grade line is called:
Velocity head
How many cubic yards of earth must be evacuated for a trench one yard wide, six ft. Deep and 300ft. Long?
200 yd3 (cubic)
What would be the most reasonable conclusion for a public water supply bacteriological sample if a coliform analysis indicates a negative fecal coliform result?
The particular sample tested did not show the presence of wastewater contamination
According to safety regulations, no worker shall enter any excavation over ________ deep unless the sides are sloped to a safe angle or proper shoring and bracing are installed.
4 feet
Which of the following sources would most likely to have a high concentration of calcium:
Lake
River
Stream
Well
Well
A connection between a safe and a potentially unsafe water supply is called a:
Cross connection
Potable water may be defined as:
Any water which according to recognized standards is safe for human consumption
Water mains should have fittings blocked when there is a change in direction of the pipe because the pressure and velocity of the water will tend to separate the joints. Methods for blocking are:
Concrete thrust blocks
Grip rings on MJ joints
Shackle Rods
Restrained joint pipe
A cutoff is normally installed between the tap on the main and the meter in service line. This fitting is called a:
Curb stop
The primary purpose of cementing the casing in a well is to:
Prevent contamination or degradation of water quality.
What condition would be a major factor in water contamination through cross connection
Turning off the water supply to a multi story building and allowing the building water supply to drain
Why must the relief port of a Reduced-Pressure Principal Blackflow Prevention Assembly NEVER be plugged or extended?
So the assembly will functioned as designed
What is the potential cross-connection hazard from sprinkler system?
HIGH Hazard
A direct water connection to a chemically compounded boiler must be connected by:
A reduced pressure principle backflow prevention device.
An exhaust fan in a chlorinator room must remove air from:
Floor level
Which of the following must be replaced when connecting a new chlorine cylinder?
Lead or fiber washers
The principal purpose of a fuse or circuit breaker in an electrical circuit is to:
Burn out or disconnect before the current gets sufficiently high to destroy the circuit wire or injure the electric apparatus
Which one of the following pump types may be damaged if it is started with the discharge valve closed?
Axial flow pump
Centrifugal pump
Positive displacement pump
Turbine pump
Positive displacement pump
Lantern rings are used to:
Lubricate packing
A self contained breathing apparatus should have a:
Positive pressure demand
The titration method could be used to measure:
Alkalinity
Chlorine residents
Dissolved oxygen
Total hardness
One purpose of water storage tanks is to:
Supply water at peak demands
The most common warning devices used in major street construction include all the following except:
Permanent street barricades
When two or more pressure reducing valves of different sizes are used in parallel, the purpose is to:
Handle wide range of flow rates
All abandoned wells should be plugged to protect the water bearing formation against possible contamination of existing or future groundwater supplies in the vicinity. The accepted method of plugging is to:
Return the well hole to the controlling geological conditions that existed before the well was drilled by completely with puddled clay or other acceptable material (bentonite)
The difference between the amount of chlorine added and the amount measured in the distribution system is called:
Demand
Two common causes of vibration that can occur with a centrifugal pump are:
Misalignment and bearing failure
In case of civil disturbance, it may be necessary to valve off a portion of the distribution system until repairs can be made. If so, which of the following would NOT be recommended?
Valve off as large of an area as possible
Which one of these factors does NOT contribute to pipeline leakage in the distribution system?
Age of the pipe system
Classification of the pipe system
Ground conditions
Prevailing system pressures
Classification of the system
Which of the following is not a purpose of certification programs?
Guaranteeing water works operators security in their current position
Visual messages or pictures are:
Often underestimated as to their effectiveness.
Which of the following items would not be considered in the budget for a water utility?
Anticipated costs due to labor and maintenance
Anticipated revenues from water sales
Coats of street maintenance
Insurance
Costs of street maintenance
Past records indicate a certain job takes two people ten hours to complete. How long would it take a crew of five people?
4 hours
1 person = 20 hours
5 persons / 20 hours = 4 hours
Using a labor cost of $19.40 per people hour, what would be the labor cost of a job that requires two people 10 hours to complete?
$388.00
Requires 20 people hours
2 person @ $19.40 per hour * 10 hours = $388
How should complaints pertaining to taste and odor be handled by field maintenance personnel?
Make a note of the problem and refer it to management for correction and report back to the customer.
Ground water generally requires less treatment than surface water for:
Microorganism
According to the USEPA regulations, the owner or operator of a public water system that fails to comply with applicable monitoring requirements must give notice to the public within:
Three months of the violation
The difference between the static water level of a well and the pumping water level is called:
Draw down
Which of the following is NOT a primary contaminant of drinking water?
Arsenic
Iron
Lead
Mercury
Iron
The possible corrosive nature of water supply upon metals may be indicated by the:
Langlier index (PH index)
Which of the following materials is NOT used for removing tastes and odors from water?
Activated Carbon
Chlorine
Chlorine Dioxide
Sulfuric Acid
Sulfuric Acid
The SWDA defines a public water system that supplies piped water for human consumption as one that has:
15 service connections or serves 25 or more people for 60 or more days per year.
When a chemically unstable water exists in the distribution mains, all or part of the following conditions may be present. Choose the one item that is LEAST LIKELY to occur.
Corrosion High pressures Incrustation Reduced flow Red water
High pressures
When iron is a problem, it is most severe in:
Dead end mains
Red water problems are primarily due to:
Iron
Hydrogen sulfide in water will cause the water to have an odor similar to:
Rotten eggs
The yield of a well could be affected by several factors, including:
Soil permeability
Depth of soil layers
Rates of groundwater movement
Dry-barrel fire hydrants have their operating valves:
In the base
The drain holes in a hydrant are designed to:
Remove water from the hydrant to prevent freezing
The outlet of a bubbler-tube type level sensing device is usually placed:
Below the lowest water level
What type of level sensor cannot be used where the water body freezes?
Float mechanism
Automation of a water system should provide:
Constant pressure
Water system automation does NOT:
Reduce the number of leaks
Water system automation DOES:
Increase reliability of the system
Provide better service to the consumer
Provide continuous positive pressure to the customer.
Reduce the cost of operation for the functions performed.
Which of the following responds to and displays information?
Secondary instruments
Which of the following is NOT a type of meter?
Centrifugal
Current
Positive displacement
Proportional
Centrifugal
The type of displacement meter most commonly used on domestic services is:
Nutating disc
A compound meter is a device which:
Combines both a displacement type and turbine type meter to get accuracy over a wide range of flows.
Eight boxes of packing for pumps were delivered, and the invoice showed $15.93 each. What is the cost of the packing?
$127.44
A chlorine gas leak may be detected with:
Aqua Ammonia
A chlorine cylinder valve is thought to be leaking. If aqua ammonia vapor is passed over the valve, the presence of a leak would be indicated by:
White vapor
When using a 150lb. cylinder, it is not advisable to draw more than_______ pounds of chlorine from any one cylinder in a 24 hour period.
42 pounds
Freezing hazard/velocity
The temperature at which a chlorine cylinders fusible plug will melt is:
160 degrees F
If a uniform dose of 1.2mg/L of chlorine is applied to a flow of 7 million gallons/day, how many pounds of chlorine will be used in one day?
70 pounds
Pounds per day formula
All persons working in a construction area or entering a construction area are required to wear the following?
Gloves
Hard Hats
Safety Glasses
Safety Shoes
Hard Hats
A system that pumps water into a sealed tank or reservoir that also contains air is called a:
Hydropneumatic system
There are several factors that could affect the accuracy of a meter. Even something as simple as location can have an effect due to:
Possible heat
Groundwater elevation
High flows
Turbulence
Turbulence
Air vacuum relief valves should be installed:
On all high points of a water main.
The difference between the the water supplied to a distribution system and the sum of metered and estimated flow consumed in the same system is generally referred to as:
Unaccounted for water
The most important factor in effective communication is:
Mutual understanding of information
