Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community for help and clear up your study doubts
Discover the best universities in your country according to Docsity users
Free resources
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
WATER DISTRIBUTION TEST 2025 QUESTIONS AND ANSWERS GRADED A+ (BRAND NEW) What does a C value of 140 means for a pipe? The pipe interior is very smooth. Which primary contaminant causes Blue Baby Syndrome? Nitrate. What is a nutating disc? Type of a water meter for a small-diameter domestic service. What causes hardness in water? Magnesium and calcium. Which of the following is a confined aquifer with groundwater under positive pressure? Artesian.
Typology: Exams
1 / 17
This page cannot be seen from the preview
Don't miss anything!
What does a C value of 140 means for a pipe?
The pipe interior is very smooth.
Which primary contaminant causes Blue Baby Syndrome?
Nitrate.
What is a nutating disc?
Type of a water meter for a small-diameter domestic service.
What causes hardness in water?
Magnesium and calcium.
Which of the following is a confined aquifer with groundwater under positive pressure?
Artesian.
____________ is an imaginary surface to which groundwater rises inder hydrostatic pressure in wells.
Piezometric surface.
If chlorine was added to water, but there is no chlorine residual, which statment is true?
Chlorine demand has not been met.
What is true about chlorine gas?
Chlorine has is 2.5 times heavier then air.
When is a ladder required in a trench?
When the trench is 4 feet or deeper?
What is the definition of diurnal pattern?
Daily pattern of water demand.
Why is trihalomethane considered a threat to human health?
Carcinogen
What is a thermocline?
A steep temperature gradient in a body of water such as a lake, marked by a layer above and below which the water is at different temperatures.
What is the name of the document that contains information about chemicals, including instructions for safe use and hazards associated with chemical?
MSDS or SDS
Which of the following I is a disinfection by-product?
THM
What is coliform bacteria?
Indicator organism
What is the name of the water that is acquired with title to land?
Riparian.
What is the best to prevent back flow?
Air gap.
What should you do if you encounter a pump with a slight leak at the packings?
Do nothing. The slight leak is required to cool and lubricate the packings.
What is the most common valve in the water distribution system?
Gate valve.
Which disinfectant is fairly weak, but will last long time in the distribution system?
Chloramine
Corrosion control to protect metals, such as pipelines and tanks.
Where is the location of the operating valve on a dry barrel hydrant?
Bottom of hydrant.
What is equal to 1 mg/L
1 ppm
Under the Lead and Copper Rule, who long are you required to keep the water in the lateral before you draw a sample?
At least 6 hours.
What is most commonly used to control algae growth in a reservoir?
Copper sulfate.
What is the purpose of priming a pump?
To fully submerge the impeller in water and remove the air inside the pump.
Which of the following is a mechanical coupling?
Victaulic
What is chlorine residual?
Chlorine remaining in the water after chlorine demand has been met.
What is the term used to describe the depression of the water table near a well during pumping?
Cone of depression.
Which of the following is an aquifer with impermeable layers above and below the aquifer, causing it to be under pressure?
Confined aquifer.
What is the benefit of looping a water main?
Improves water quality and flow.
Which of the following is a moderately flexible pipe with smooth interior surface, good flow factor, light weight, and least susceptible to corrosion?
PVC Pipe.
What is the minimum required chlorine residual concentration for effluent leaving a water treatment plant and entering a distribution system?
0.2 mg/L
What is the specific capacity of a well?
Well yield per unit of drawdown.
What is the purpose of a lantern ring?
Distributes water uniformly around the shaft to provide lubrication and cooling.
What is one of the main benefits of using steel pipe in the distribution system?
Strength.
What is a preventive maintenance program?
Detecting and correcting problems before equipment breaks down.
Which backflow preventer is suitable for any type of cross-connection?
Reduced pressure zone backflow preventer.
Which of the following best describes a positive displacement water meter?
Measures the volume of the water passing through the flowmeter by repeatedly entrapping water in order to measure flow.
Which water meter is a pressure differential type?
Venturi.
What is the primary reason for installing a service lateral on a water main at a 45- degree angle?
To prevent sediments and air from entering the service lateral.
What is the most common disinfectant used n the water industry?
Chlorine.
Which valve is used to release small pockets of air that gather at the high points of a pipeline?
Air release valve.
What is the purpose of a hydropneumatic tank?
Maintain water pressure in the system and control the operation of the pump, typically in small water systems.
What should you do to a new sample bottle before you collet a sample?
Do nothing. Sample bottles are ready for use.
Which of the following is true when collecting a sample for biological contaminants?
Leave a one-inch gap at the top of the bottle.
What is the action level for lead (based on the 90th percentile level of tap water samples)?
0.015 mg/L
What is percolation?
Slow passage of water through soil.
Which of the following is a presence / absence lab test for coliform?
Colilert.
Which of the following is a toxic gas that smells like rotten eggs?
Hydrogen sulfide.
What is the radius of influence?
The radial distance from the center of the well to the point where there is not lowering of the water table.
Which of the following is not a requirement of the lock-out / tag-out procedure?
All employees must sign the tag.
Drinking water standars are based on:
Maximum Contaminant Level.
What is the maximum allowable chlorine residual in the water distribution system?
4 mg/L
Which rule was implemented to improve public health protection by reducing fecal pathogens to minimal levels in the drinking water supply?
Total Coliform Rule.
What is required when a water sample test positive for a total coliform?
Grab another sample from the same location. Additionally, grab a sample upstream and downstream of this location.
Which pipe is the most difficult to locate below ground?
Asbestos cement pipe.
Which of the following is not a characteristic of a confined space?
A space that is intended for a long-term occupancy.
What should be the minimum flushing velocity for a water distribution system?
2.5 ft/s.
