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Water

Drinking Water - Drinking Water Terms and Acronyms

Click on the applicable letter to go to terms/acronyms that start with that letter

A B C D E F G H I J
K L M N O P Q R S T
U V W X Y Z  

(Alphabetized by Term/Acronym)

A

Action Level (AL) The concentration of a contaminant that, if exceeded, triggers treatment or other requirements that a water system must follow.
Acute Health Effect An immediate (within hours or days) effect that may result from exposure to certain drinking water contaminants.
ACWA American Clean Water Association
APWA American Public Works Association
Aquifer A natural underground layer that contains water.
Artificial Filter Filter material that is placed in the annular space to increase the effective diameter of the well, and to prevent fine-grained sediments from entering the well.
ASDWA Association of State Drinking Water Administrators
Aquifer Storage and Recovery Well (ASR) A water well that allows potable water to be injected into a subsurface aquifer to be recovered by pumping at a later date.
ATSDR Agency for Toxic Substances and Disease Registry
AWRA American Water Resources Association
AWWA American Water Works Association

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B

Backflow Prevention Device A safety device used to prevent contamination of the potable water supply from the reverse flow of water from an irrigation system or other customer activity back into the potable distribution system.
BAT Best Available Technology: the best technology, treatment techniques, or other means available, while taking cost into consideration. 
Bedrock Parent solid rock formation underlying weathered rock and soil.
Billing Cycle The regular interval of time when customer’s bills are issued, generally every month (monthly) or two months (bimonthly).
BMP Best Management Practice(s)
Boil Water Notice/Advisory A notice, whether written or verbal, issued by the Department, or the owner or operator of a public water system, notifying the users of the water system that the water is/may be contaminated and to boil the water (vigorous rolling boil for at least one minute) prior to using it for drinking or cooking. The notice shall give the reason for its issuance and corrective actions being taken.
Booster Pump Any pump installed within a water distribution system for the purpose of increasing the water pressure in the water distribution system.
Business Plan A document consisting of three sub plans; a “Facilities Plan”, a “Management Plan”, and a “Financing Plan” which is intended to show how a water system will be self-sustaining, and have the commitment and the financial, managerial and technical capability to consistently comply with the State Safe Drinking Water Act.

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C

CAP Corrective Action Plan
CCR Consumer Confidence Report: An annual water quality report to be supplied to all customers of Community Public Water Systems, summarizing information regarding sources used, any detected contaminants, compliance and educational information.  The CCR is due to customers by July 1st of each year.
CDBG Community Development Block Grant
CEE Center for Environmental Education
Certified Laboratory A laboratory approved by DHEC or EPA to conduct water analyses.
Certified Tester Any person holding an up-to-date backflow prevention assembly tester certification card issued by DHEC.
Certified Well Driller Any person currently certified by the State Environmental Certification Board to practice as a well driller in South Carolina.
CFC Chlorofluorocarbons
CFM Chlorofluoromethanes
CFR Code of Federal Regulations
Check Valve A valve that allows flow in only one direction, preventing backflow.
Chronic Health Effect The possible result of exposure over many years to a drinking water contaminant at levels above its MCL.
CM Corrective Measure
Coagulation A process using coagulant chemicals and mixing by which colloidal and suspended materials are destabilized and agglomerated into flocs.
Coliform Bacteria A group of related bacteria whose presence in drinking water may indicate contamination by disease-causing microorganisms.
Combined Distribution System The interconnected distribution system consisting of the distribution systems of wholesale systems and of the consecutive systems that receive finished water.
Community Water System A water system that supplies drinking water to 25 or more of the same people year-round in their residences.
Compliance The act of meeting all state and federal drinking water regulations.
Connection Fee A charge assessed to a new account by a water utility that generally covers the cost of hooking up to the system and compensates the utility for prior water system improvements that made the capacity available.
Contaminant Anything found in water (including microorganisms, minerals, chemicals, radionuclides, etc.) that may be harmful to human health.
CPE: Comprehensive Performance Evaluation A thorough review and analysis of a treatment plant’s performance-based capabilities and associated administrative, operation and maintenance practices. It is conducted to identify factors that may be adversely impacting a plant’s capability to achieve compliance and emphasizes approaches that can be implemented without significant capital improvements.
Cone of Depression The depression in the water table or potentiometric surface in an aquifer caused by pumping water from a well and usually having the shape of an inverted cone.
Consecutive System A public water system that receives some or all of its finished water from one or more wholesale systems. Delivery may be through a direct connection or through the distribution system of one or more consecutive systems.
Conventional Filtration Treatment A series of processes including coagulation, flocculation, sedimentation, and filtration resulting in substantial particulate removal.
Corrosion Inhibitor A substance capable of reducing the corrosivity of water toward metal plumbing materials, especially lead and copper, by forming a protective film on the interior surface of those materials.
Cross-connection Any actual or potential connection or structural arrangement between a public water supply and any other source or system through which it is possible to introduce into any part of the potable system any used water, industrial fluid, gas or substance other than the intended potable water which the system is supplied. Bypass arrangements, jumper connections, removable sections, swivel or changeover devices and other temporary or permanent devices through which or because of which backflow can or may occur are considered to be cross-connections.
Cryptosporidium A microorganism commonly found in lakes and rivers, which is highly resistant to disinfection, and can cause gastrointestinal illness with symptoms that include diarrhea, nausea, and/or stomach cramps.
CT or Ctcalc The product of “residual disinfectant concentration” in mg/L determined before or at the first customer, and the corresponding “disinfectant contact time” in minutes. If a public water system applies disinfectants at more than one point prior to the first customer, it shall determine the CT of each disinfectant sequence before or at the first customer to determine the total percent inactivation or “total inactivation ratio”. A total inactivation ratio equal to or greater than 1.0 is assumed to provide a 3-log inactivation of Giardia lamblia cysts.
Cu Copper
CSGWPP Comprehensive State Ground Water Protection Program
CSI Compliance Sampling Inspection
CWA Clean Water Act (aka FWPCA: Federal Water Pollution and Control Act)

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D

DBP Disinfection By-Product
DDT DicholoroDiphenylTricholoroethane
Dedicated Fire Line A water line connected to a public water system that is designed and used solely for a fire protection system. Such lines must be provided with an acceptable and approved backflow prevention device and must not connect at any point downstream of that device with water lines or fixtures that are used for potable water.
Desalination The process of removing salt from brackish water or sea water, producing water suitable for fresh water uses and concentrated brine.
Developed Water Water that has been captured in reservoirs, diverted from rivers/streams, or accessed by wells for use by society.
Development Repairing damage to the aquifer caused by drilling procedures and increasing the porosity and permeability of the geologic materials surrounding the intake portion of the well.
Direct Filtration A series of processes including coagulation and filtration but excluding sedimentation resulting in substantial particulate removal.
Disinfection A chemical (commonly chlorine, chloramines, or ozone) or physical process (ultraviolet light) used in any part of the treatment or distribution process, that is intended to kill or inactivate pathogenic microorganisms such as bacteria, viruses, and protozoa.
Disinfectant Contact Time The time in minutes that it takes for water to move from the point of disinfectant application or the previous point of disinfectant residual measurement to a point before or at the point where residual disinfectant concentration is measured.
Disinfected The water is free of harmful or pathogenic organisms.
Dispensing Station A facility where additional treatment is provided to water from an approved public water system, and that treated water is available to the general public.
Distribution System A network of pipes leading from a treatment plant to customers’ plumbing systems.
Distribution Treatment Plant Any facility located within a distribution system capable of altering the physical, chemical, radiological, or bacteriological quality of the water in a public water system.
DPD Method of Measuring Chlorine Residual in Water
DWSRF Drinking Water State Revolving Fund

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E

EDB Ethylene Dibromide
EDC Ethylene Dichloride
EJ Environmental Justice
Emergency Well A well that is operable and connected to the distribution system, but is not routinely operated or sampled. Such wells are only available to be used during emergency situations and only in conjunction with a boil water advisory.
EPA Environmental Protection Agency (US Government)
ERT Emergency Response Team
Exemption State or EPA permission for a water system not to meet a certain drinking water standard, giving the system additional time to obtain financial assistance or make improvements in order to come into compliance with the standard.

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F

Facilities Plan A document that consists of an assessment of the current and foreseeable water supply needs of a water system’s service area; a detailed description of alternatives considered for meeting those needs; detailed cost estimates for the construction, operation and maintenance of the different alternatives, and the rationale for the alternative selected.
Fecal Coliform The coliform bacteria group that is present in the intestinal tracts and feces of humans and other warm-blooded animals. Drinking water with fecal coliform can cause diarrhea and other gastrointestinal illnesses.
FEMA Federal Emergency Management Agency
Filtration A water treatment process that involves water passing through sand or other media, where particles and other constituents are trapped and removed from the flow.
Finished Water Water that has been treated and is ready to be delivered to customers.
Fire Flow Five hundred (500) gallons per minute, or the flow required for fire protection by the local government or public water system, whichever is greater.
First Draw Sample A one-liter sample of tap water, collected in accordance with R.61-58.11 (H)(2), Sample Collection Methods, that has been standing in plumbing pipes at least 6 hours and is collected without flushing the tap.
Flocculation A process to enhance agglomeration or collection of smaller floc particles into larger particles that will settle more easily through gentle stirring by hydraulic or mechanical means.
Flow Rate The rate at which a volume of water flows through pipes, valves, etc. in a given period of time. Often reported as cubic feet per second (cfs) or gallons-per-minute (gpm).
FMP Facility Management Plan
FOIA Freedom of Information Act
FWPCA Federal Water Pollution and Control Act (aka CWA: Clean Water Act)
FY Fiscal Year

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G

GAC Granular Activated Carbon
Giardia lamblia A microorganism frequently found in rivers and lakes, which, if not treated properly, may cause diarrhea, fatigue, and cramps after ingestion.
Gpd Gallons per day
Gpm Gallons per minute
Ground Water The water that systems pump and treat from aquifers (natural reservoirs below the earth’s surface).
Groundwater Recharge Percolating or injecting surface water into a groundwater basin to increase the available groundwater supply.
Groundwater Treatment Plant Any facility capable of altering the physical, chemical, radiological or bacteriological quality of groundwater for public consumption in a public water system.
Gross Alpha Particle Activity The total radioactivity due to alpha particle emission as inferred from measurements on a dry sample.
Gross Beta Particle Activity The total radioactivity due to beta particle emission as inferred from measurements on a dry sample.
Ground Water Rule (GWR) EPA issued rule that provides additional protection from disease-causing microorganisms in public water systems with a groundwater source.
GWPC Ground Water Protection Council
Ground water under the direct influence of surface water (GWUDI) Any water beneath the surface of the ground with significant occurrence of insects or other microorganisms, algae, or large-diameter pathogens such as Giardia lamblia, or Cryptosporidium, or significant and relatively rapid shifts in water characteristics such as turbidity, temperature, conductivity, or pH, which closely correlate to climatological or surface water conditions.

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H

Health Advisory (HA) An EPA document that provides guidance and information on contaminants that can affect human health and that may occur in drinking water, but which EPA does not currently regulate in drinking water.
Haloacetic Acids (HAA) A by-product of disinfecting drinking water that is regulated by the USEPA.
HAD Health Assessment Document
HAZMAT Hazardous Materials
HBFC Hydrobromofluorocarbons
HC Hydrocarbon
HCFC Hydrochlorofluorocarbon
HFC Hydrofluorocarbon
HOC Halogenated Organic Carbons
Hydrologic Cycle Movement of water as it evaporates from rivers, lakes or oceans, into the atmosphere, returning to earth as precipitation, flowing into rivers to the ocean and evaporating again.

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I

Inorganic Contaminants Mineral-based compounds such as metals, nitrates, and asbestos. Some are naturally occurring, but can also enter water through farming, chemical manufacturing, and other human activities. EPA has set legal limits on 15 inorganic contaminants.

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L

Leak Detection Pinpointing the exact location of leaks from water pipes and fittings
Leak Management Organized, proactive functions of a water system to control distribution system leakage. Includes flow analysis, pressure management and leak detection and repair, and system rehabilitation.
LCR Lead and Copper Rule
LLR Department of Labor, Licensing and Regulation responsible for licensing water operators and well drillers.
Low Flow Detector Part of a water meter register that indicates any flow through the meter (leak indicator).
Locational Running Annual Average (LRAA) Average of sample analytical results for samples taken at a particular monitoring location during the previous four calendar quarters.

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M

Master meter Single meter that measures utility usage for an entire property or an entire building.
Maximum Contaminant Level (MCL) The highest level of a contaminant that EPA allows in drinking water. EPA sets MCLs at levels that are economically and technologically feasible.
Maximum Contaminant Level Goal (MCLG) The level of a contaminant at which there would be no risk to human health. This goal is not always economically or technologically feasible, and the goal is not legally enforceable.
Maximum Residual Disinfectant Level (MRDL) A level of a disinfectant added for water treatment that may not be exceeded at the consumer’s tap without an unacceptable possibility of adverse health effects. 
Maximum Residual Disinfectant Level Goal (MRDLG) The level of a drinking water disinfectant below which there is no known or expected risk to health.
Microorganisms Tiny living organisms that can be seen only with the aid of a microscope (also called microbes). Some microorganisms can cause acute health problems when consumed in drinking water.
Mixed Use Meter A water meter that serves more than one type of end use, such as an office building and its surrounding landscape.
Monitoring Required testing that water systems perform to detect and measure contaminants. A water system that does not follow EPA’s monitoring methods or schedule is in violation, and may be subject to legal action.

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N

National Primary Drinking Water Regulations Primary drinking water regulations promulgated by the Administrator pursuant to the Federal Act and contained in 40 CFR Part 141, as amended.
National Secondary Drinking Water Regulations Secondary drinking water regulations promulgated by the Administrator pursuant to the Federal Act, and contained in 40 CFR Part 143, as amended.
NCWS Non-Community Water System
Non-Coliform Growth (NCG) Any bacterial growth other than coliform type that appears in a membrane filter test for coliform bacteria.
NIPDWR National Interim Primary Drinking Water Regulations
NOI Notice of Intent
Non-Detects Laboratory analysis indicates that the constituent is not present (ND).
Non-Community Water System A public water system which serves at least fifteen (15) service connections or regularly serves an average of at least twenty-five (25) individuals daily at least sixty (60) days out of the year, and does not meet the definition of a community water system.
Non-Transient Non-Community Water System (NTNCWS) A water system that supplies water to 25 or more of the same people at least six months per year in places other than their residences. Examples include schools, factories, office buildings, and hospitals that have their own water systems.
Not applicable (NA) Does not apply to this situation
Non-Potable Water Water that does not, or may not, meet drinking water quality standards.
Non-Revenue Water The volume of unbilled water consumption (fire fighting, system flushing, etc.) added to real losses and apparent losses included in water audits.

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O

Operator A person certified by the South Carolina Environmental Certification Board as being qualified to operate and maintain a public water system. Operation and maintenance responsibilities shall include, but not be limited to, conducting tests of the raw and treated water, adjusting chemical feed rates, and/or operating equipment so as to change the physical, chemical, radiological or bacteriological quality of surface or ground water to meet established standards.
Optimal Corrosion Control Treatment The corrosion control treatment that minimizes the lead and copper concentrations at users’ taps while insuring that the treatment does not cause the water system to violate any national primary drinking water regulations.
Organic Contaminants Carbon-based chemicals, such as solvents and pesticides, which can get into water through runoff from cropland or discharge from factories. EPA has set legal limits on 56 organic contaminants.
O & M Operations and Maintenance

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P

Pathogen A disease-causing organism.
Pb Chemical symbol for lead
PCB Polychlorinated Biphenyl
PCE Perchloroethylene
Peak Use The maximum demand occurring in a given period, such as hourly, or daily, or annually.
Per Capita Residential Use Average daily water use (sales) to residential customer divided by population served.
Picocurie (pCi) The quantity of radioactive material producing 2.22 nuclear transformations per minute.
Pollution Source A facility or activity that may introduce any dangerous material to the groundwater system below the water table in concentrations sufficient to cause drinking water quality standards to be exceeded or to decrease the quality of the drinking water
Point-of-Entry Treatment Device (POE) A treatment device applied to the drinking water entering a house or building for the purpose of reducing contaminants in the drinking water distributed throughout the house or building.
Point-of-Use Treatment Device (POU) A treatment device applied to a single tap used for the purpose of reducing contaminants in drinking water at that one tap. Examples include granulated activated carbon filters, reverse osmosis filters and ion-exchange water softening devices.
Point-of-Use Meter A meter that measures water flow at the actual usage point, such as a faucet or toilet.
Potable water Water that meets federal and state water quality standards for water delivered to utility customers.
Pounds Per Square Inch (PSI) A unit for pressure exerted by water in a distribution system.
PPB Parts per billion, also micrograms per liter (ug/l)
PPM Parts per million, also milligrams per liter (mg/l)
Pressure regulation Maintaining distribution system water pressure within certain limits.
Primary Drinking Water Regulation The maximum contaminant limits, the requirements for monitoring, the requirements for reporting, record retention requirements and public notifications specified in R.61-58.5 and R.61-58.6.
Primacy States that have the responsibility and authority to administer EPA’s drinking water regulations. The state must have rules at least as stringent as EPA’s.
Professional Engineer A person properly qualified to perform engineering work as provided in Title 40 of the 1976 code of Laws of South Carolina, as amended, Chapter 22, Engineers and Land Surveyors.
Professional Geologist A person registered as a professional geologist by the South Carolina State Board of Registration for Geologists.
Public Notification An advisory distributed to affected consumers when a system has violated MCLs or other regulations. The notice advises consumers what precautions, if any, they should take to protect their health.
Public Service Announcement (PSA) An inexpensive or free advertisement or message on mass media that serves the public good.
Public Water System (PWS)
  1. Any public or privately owned waterworks system that provides drinking water, whether bottled or piped, for human consumption, including the source of supply whether the source of supply is of surface or subsurface origin.
  2. All structures and appurtenances used for the collection, treatment, storage, or distribution of drinking water delivered to consumers.
  3. Any part or portion of the system and including any water treatment facility which in any way alters the physical, chemical, radiological, or bacteriological characteristics of drinking water; provided, that public water system shall not include a drinking water system serving a single private residence or dwelling.

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R

Running Annual Average (RAA) The average of a chemical level for the past four consecutive quarters used to determine if the water system meets water quality standards.
Radionuclides Any man-made or natural element that emits radiation and that may cause cancer after many years of exposure through drinking water.
Raw Water Water in its natural state, prior to any treatment for drinking (also called source water).
REM The unit of dose equivalent from ionizing radiation to the total body or any internal organ or organ system. A millirem (MREM) is one one-thousandth of a rem.
Residual Disinfectant Concentration The concentration of disinfectant measure in mg/L in a representative sample of water.
Reverse Osmosis (RO) A water treatment unit that forces water through several membranes to remove various chemicals and contaminants.

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S

Sample The water that is analyzed for the presence of EPA-regulated drinking water contaminants. Depending on the regulation, EPA requires water systems and states to take samples from source water, from water leaving the treatment facility, or from the taps of selected consumers.
Sanitary Seal A cap on the top of the well casing usually fitted with a rubber expansion gasket, which seals off surface drainage, thereby protecting the well from contamination directly down the casing.
Sanitary Survey An on-site review of the water sources, facilities, equipment, operation, maintenance, and record keeping of a public water system for the purpose of evaluating the adequacy of the facilities for producing and distributing safe drinking water.
Secondary Containment A basin constructed to receive the liquids spilled from any chemical storage tank or solution tank, designed to prevent migration of any accumulated liquid out of the basin to the soil, ground water, or surface water at any time. The volume of the secondary containment shall equal or exceed the volume of the tank.
Secondary
Drinking Water Standards
Non-enforceable federal guidelines regarding cosmetic effects (such as tooth or skin discoloration) or aesthetic effects (such as taste, odor, or color) of drinking water.
SDWA Safe Drinking Water Act
SDWIS Safe Drinking Water Information System
SMCL Secondary Maximum Contaminant Level: The maximum contaminant levels, which, in the judgment of DHEC are requisite to protect the public welfare from adverse odor or appearance of water.
SOC Synthetic Organic Chemical: Man-made organic compounds created through industrial processes. Some SOCs evaporate easily (are volatile) while others tend to remain dissolved in water, including pesticides and herbicides.>
Sole Source Aquifer An aquifer that supplies 50 percent or more of the drinking water of an area.
Source Water Water in its natural state, prior to any treatment for drinking (also called Raw Water).
Source Water Protection Protecting drinking water from pollution and contamination at its source, including wellhead protection and watershed protection.
SPDWR State Primary Drinking Water Regulations R.61-58
SRF State Revolving Fund offers low interest loans to drinking water facilities for upgrades and/or improvements to their systems.
State Water System (SWS) Any water system that serves less that fifteen (15) service connections and regularly serves an average of less than twenty-five (25) individuals daily.
Storm drainage Surface runoff of water resulting from rain or snowstorms.
Surface Water Water that systems pump and treat from sources open to the atmosphere, such as rivers, lakes, and reservoirs.
SWTR Surface Water Treatment Rule

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T

Tap A service connection, the point at which water is delivered to the consumer (building, dwelling, commercial establishment, camping space, industry, etc.) from a distribution system, whether metered or not, and regardless of whether there is a user charge for consumption of the water.
TCE Tricholorethylene
TCR Total Coliform Rule
TDS Total dissolved solids
THM: Trihalomethanes A group of chemicals that are a reaction by-product when chlorine is added as a disinfectant to water containing organic materials. These chemicals are called disinfection by-products and are regulated by the USEPA. Some are suspected carcinogens.
Total Organic Carbon (TOC) Total organic carbon in mg/L measured using heat, oxygen, ultraviolet irradiation, chemical oxidants, or combinations of these oxidants that convert organic carbon to carbon dioxide.
Transient, Non-Community Water System (TNCWS) A water system that provides water in a place such as a gas station or campground where people do not remain for long periods of time. These systems do not have to test or treat their water for contaminants that pose long-term health risks because fewer than 25 people drink the water over a long period. They still must test their water for microbes and several other chemicals.
Treatment technique (TT) A required process intended to reduce a contaminant in drinking water that is above the maximum contaminant level (MCL).
Turbidity The cloudy appearance of water caused by the presence of tiny particles. High levels of turbidity may interfere with proper water treatment and monitoring.

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U

UST Underground Storage Tank
Utility Used alternately to describe a provided resource, such as water, gas, and electric, as well as for the provider of the resource.

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V

Valve Device to control the flow of water.
Variance State or EPA permission not to meet a certain drinking water standard. The water system must provide that, due to the characteristics of the raw water, it cannot meet the MCL, even while using the best available treatment method, and the variance will not create an unreasonable risk to public health.
Viable Water System A water system that is self-sustaining and has the commitment and the financial, managerial, and technical capability to consistently comply with the State Safe Drinking Water Act.
Violation A failure to meet any state or federal drinking water regulation.
VOC Volatile Organic Compounds examples of which include petroleum-based products like gasoline and benzene.
Vulnerability Assessment (VA) An evaluation of drinking water source quality and its vulnerability to contamination by pathogens, toxic chemicals, and terrorist attacks.

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W

Water Audit A thorough examination of the accuracy of water agency records and system control equipment to identify, quantify, and verify the water and revenue losses.
Water losses The physical loss of water from the distribution system prior to reaching the customer. Includes leakage from piping and reservoir walls, and storage overflows caused by faulty control equipment or operator error. Water losses represent a waste of water and energy.
Watershed The land area from which water drains into a stream, river, or reservoir.
Water Softener A device that reduces water hardness by replacing calcium and magnesium ions with sodium ions.
Water Use Efficiency A measure of the amount of water used versus the minimum amount required to perform a specific task.
Wellhead Protection Area (WHPA) The area surrounding a drinking water well or well field which is protected to prevent contamination of the well(s).
WHPP Wellhead protection program: a program designed by a water system to protect the area surrounding a drinking water well.
Wholesale system A public water system that treats source water as necessary to produce finished water and then delivers some or all of that finished water to another public water system.

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