DefinitionA community water system (CWS) is a public water system that serves at least 15 service connections used by year-round residents or regularly serves at least 25 year-round residents.
The public water use index provides some data to explore the relative importance of community water supplies as sources of drinking water and to provide context for subsequent CWS indicators/contaminants. The Safe Drinking Water Act (SDWA) requires data to be collected by the Safe Drinking Water Information System (SDWIS) for a number of different types of public water systems of which CWS are a subset. The CWS represent non-transient public water systems that serve year round community residents. The range of state populations served by CWS as their primary residential drinking water source varies from 95% to as low as 40% within the United States. (Modified from the National Environmental Public Health Tracking Network [NEPHTN] Nationally Consistent Data and Measures [NCDM] public water use document, version 3)
NumeratorEstimated population in each community water system based on number of connections. Estimations provided by the Division of Drinking Water (DDW) within the Utah Department of Environmental Quality (UDEQ).
DenominatorNo rates provided, not applicable.
Data Interpretation IssuesPopulation estimates are rough and may overestimate or underestimate the number of affected people. The estimates are based on the number of connections served by community water systems (CWS) that report to the Utah Department of Environmental Quality (UDEQ).
Data reported to other sources, such as the Environmental Protection Agency (EPA), may differ slightly.
The current measure is derived for CWS only. Private wells are another important source of population exposure to water contaminants. Transient non-community water systems, which are regulated by the EPA, may also be an important source of potential exposure. (From the National Environmental Public Health Tracking Network [NEPHTN] Nationally Consistent Data and Measures [NCDM] public water use document, version 3)
Why Is This Important?People drink and use water every day. The majority of Americans are provided with high quality drinking water. About 90% of people in the United States get their water from a community water system versus a smaller water supply, such as a household well (EPA 2013). The EPA sets regulations for treating and monitoring drinking water delivered by community water systems. There are water quality standards and monitoring requirements for over 90 contaminants. Drinking water protection programs play a critical role in ensuring high quality drinking water and in protecting the public's health.
Contaminants in drinking water have the potential to affect many people, because people drink and use water every day. The number of people served by a community water system varies from 25 to hundreds of thousands. Community water systems in the U.S. provide among the highest quality drinking water in the world. However, some contaminants are present at low levels, and there is a possibility that drinking water can become contaminated at higher levels. If a person is exposed to a high enough level of a contaminant, they may become ill. Effects can be short-term or long-term and depend on the specific contaminant, the level of contaminant in the water, and the person's individual susceptibility. As additional information is obtained about how specific contaminants affect public health, standards may change in order to better protect public health.
The purpose of this Indicator Report is to show how many people drink water that have regulations on contaminant levels to reduce health-risks. The proportion of the population served by regulated community water supplies provides a measure of the estimated proportion of people in the state who are served by water that is being monitored for public health protection.