What is the Safe Drinking Water Act?


Passed by Congress in 1974, the Safe Drinking Water Act (SDWA) is the bedrock of all other US federal laws regulating the quality and safety of drinking water. It authorizes the Environmental Protection Agency (EPA) to set standards for the safety of public drinking water, and forces states to comply. This involves regulating the levels of certain contaminants that may be found in the water supply, protecting the sources of the water, and setting requirements for the purification of water in public systems.

Effect on Water Quality

Before the Safe Drinking Water Act was passed, the US had established the Clean Water Act but had no national standards for determining or enforcing the safety of drinking water. What standards existed were established at the state or local level. How strong they were and how well they were enforced varied greatly. The Safe Drinking Water Act directed the EPA to identify contaminants in drinking water supplies that presented serious health risks, set limits on how much of these contaminants would be allowed in the water, and enforce those limits. As a result, many public water supplies nationwide became safer over the next few decades.

Immediate Results of The Safe Drinking Water Act

In 1975, months after the Safe Drinking Water Act passed, the EPA began testing the municipal water supplies in 80 cities for certain chemicals identified as carcinogenic.[] These chemicals came from sources as diverse as industrial pollution, agricultural runoff, natural sources, and even chlorination, the process of adding chlorine to the municipal water supply, which was meant to kill harmful bacteria. By June 1977, all states and municipalities were required to establish systems for testing their public water for contaminants, test regularly, and inform consumers of any risks they identified.[]

How Water Sources are Protected by the Safe Drinking Water Act

Initially, the EPA focused its efforts on removing identified pollutants from public water systems. Later amendments to the SDWA expanded the efforts to protect the original sources of the water. Reservoirs, lakes, streams, and groundwater are all covered by EPA regulations under the Safe Drinking Water Act. Under these regulations, the water must be tested regularly. Identified pollutants are to be removed as much as possible. In case of serious contamination, consumers must be notified. When a source of pollution is identified (ie industry or agricultural runoff), steps must be taken to stop the pollution.

Who Enforces the Safe Drinking Water Act?

While the EPA has primary responsibility for setting and enforcing the SDWA, most of the actual work is done at the state and local level. States are required to establish standards for drinking water safety that are in line with the SDWA.