Terms Flashcards
Aquifer
A natural underground layer of porous, water-bearing materials usually capable of yielding a large amount of water
Flow Rate
Also known as GPM, is the measurement of how many gallons of water potentially flow out of something
Air Gap
An open vertical drop, or vertical empty space, that separates a drinking water supply to be protected from another water system in a water treatment plant or other location. This open gap prevents the contamination of drinking water by backsihonage or backflow because there is no way raw water or any other water can reach the drinking water
GUDI
Groundwater under direct influence of surface water
Breakpoint Chlorination
Breakpoint chlorination is the process of adding chlorine to water until the chlorine demand has been satisfied
Clearwell
Is a treated water storage tank at the treatment plant that allows the plant to operate continuously at a constant flow
Standpipe
Are tanks that stand on the ground and can provide large volumes of water at low pressures
Reservoirs
Constructed out of concrete and are either circular or rectangular in shape. They may be buried in the ground or located on the ground surface
Blow-out
Occurs when corrosion has reduced the strength of the pipe wall and where. a pressure surge causes the wall to rupture
Pinhole
Leaks that are very small holes in the pipe wall
Circumferential Break
Occur when a pipe cracks along its circumference (due to corrosion or external forces)
Cathodic Protection
This type of protection consists of a “sacrificial anode or cathode” made of zinc or magnesium. These anodes or cathodes are buried in the ground in close proximity to the pipe and in areas that are prone to external corrosion. These metals deteriorate first and thus protect the pipe material from deterioration
Water hammer
The force caused by a sudden change in water velocity
Cryptosporidium
Responsible for a diarrheal disease, and is a protozoa of major concern as a source of waterborne diseases
Heterotrophic Plate Count
Provides an indication of the level of the aerobic bacteria population. This test does not provide an indication of a pubic health risk; however, the results can be used to assess treatment efficiency and distribution system conditions
Trihalomethanes (THMs)
Are formed when chlorine interacts with naturally occurring organic compounds during chlorination. THMs are the most widely occurring synthetic organic compound found in chlorinated drinking water.
Resistance
A material’s tendency to restrict or resist the flow of current and represented by the symbol R in electrical equations
Ohm’s Law
States that in an electrical circuit, the amount of current in amperes is equal to the pressure in volts divided by the resistance in ohms.
Turbidity
The cloudiness causes by suspended matter in water and is a relative measurement of water clarity. Turbidity is health for both health and aesthetic reasons
Zebra Mussles
Are a species that are a threat to water systems because they can easily attach to water intake structures and the interior of water intake pipes. Block intake screens.
Dosage
Amount of a chemical you put in a substance
Chlorine gas
Involves using chlorine gas as the disinfectant. One method of chlorination
Chloramination
The application of ammonia and chlorine, with the addition usually after the application of chlorine.
Chlorine Demand
Any chlorine added to the water will have little or no disinfecting action, and additional chlorine must be added
Total Chlorine residual
The sum of the free chlorine residual and the combined chlorine residual is reported as the total chlorine residual
Free chlorine residual
Is formed when chlorine reacts with water to form hypochlorous acid and the hypochlorite ion
Combined chlorine residual
If there is ammonia in the water, chlorine readily reacts with it to form compounds that make up the combined chlorine residual
Surge Tanks
These tanks are not storage facilities, but are used mainly to control water hammer or to regulate the flow of water. To protect piplelines against destruction due to excess surge pressure.
unidirectional flushing
Invloves isolating specific section of the water distribution system by closing the appropriate values to force the water to flow in a single direction
UV disinfection
Most common type of non-chemcial disinfection. Used in primary disinfection of groundwater, surface water and GUDI supplies. It inactiates bacteria, viruses and cysts by penetrating cell walls and rendering the organisms unable to reproduce.
Swabs
Are made of polyurethane foam and used to clean pipes
Pig
Used to clean pipes. but increase possibility of pipe leaks (does not go oink)
Flushing
Used to remove any construction debris or sediment from the pipe. It is used to clean out distribution pipelines by removing any impurities
Corrosion
The gradual decomposition or destruction of metal material by chemicals or electrochemical reactions.
Backflow prevention
Used to prevent the backflow of non-drinking water into a water system. The type of device depends on the degree of hazard and the probability of backflow occurrence.
Double Check Valve
Composed of two internall loaded, independently acting check valved, tightly closing resilent seated shutoff valves attatched at each end of the assembly and fitted with tightly closing resilient seasted test cocks
Soil Types:
1: Hard and dense and penetrated by sharp object
2: Stiff, dense and be be penetrated by a moderately sharp object
3: Stiff to firm and compact to lose in consistency
4: Soft to very soft soil and very loose consistency
Boring
Is an alternative to trenching for the installation/repair of underground utility structures.
Tapping
Used to drill or thread holes in a pipe surface. Make connection to pipelines, tanks, and other plant piping without having to shutdown the lines
Raw water sampling requirements
- For groundwater samples should be ideally be collected from a tap located as close as possible to the wall, must be taken before the water enters any storage/pressure tank and before any treatment
- Surface water; samples must be collected prior to any chemical addition.
Volatile Organic Compounds (VOC)
DPD (Diethyl-p-phenylene diamine)
A chemical that is added to the water. It will turn the water from a light to dark pink depending o the amount of chlorine residual in the water
Butterfly Valve
Has a movable disc as large as the full diameter of the pipe. The disc rotates on a spindle or shaft in only one direction to either block or allow the flow of water
Ball valve
A movable part is a ball with a cylindrical hole bored through it. When the ball is in one position, There is a straight passenger through the valve.
Gate valves
The most common type of linear stroke valves. Its main purpose is to isolate sections of mains to permit emergency repairs without interruption of service to large numbers of customers.
SDS
A summary document that provides information about hazardous products and advice about safety precautions.
Ice removal
Electrical thawing and hot water and thawing
