Home > Major Acts of Congress > Safe Drinking Water Act (1974)

Kyle A. Loring

In 1974 Congress enacted the Safe Drinking Water Act (SDWA) (P.L. 93-523, 88 Stat. 1660) to protect the quality of both actual and potential drinking water in the United States. Congress had created the SDWA in response to a nationwide survey that revealed health risks from inadequate public water-supply facilities and operating procedures. To achieve its goal the SDWA provides water quality standards for drinking-water suppliers, protects underground drinking-water sources, and directs appropriate deep-well injection of wastes.

The SDWA requires the U.S. Environmental Protection Agency (EPA) to regulate all "public water systems," defined as systems that provide piped water for human consumption for at least sixty days a year to at least fifteen service connections or twenty-five people. The EPA does this through Primary Drinking Water Regulations, by which it first identifies contaminants that may pose a risk to human health and that occur in drinking water at potentially unsafe levels. Then the EPA specifies a Maximum Contaminant Level Goal (MCLG) for each contaminant, which is set at the level below which there is no predicted health risk. Finally the EPA creates a legally enforceable Maximum Contaminant Level (MCL), which is the greatest amount of contaminant that will be allowed in the public water supply. This MCL must be set as close as is feasible to the MCLG after taking into account the best technology, treatment techniques, and costs. Since the 1996 amendments discussed below, the EPA may instead require a Treatment Technique for removing the contaminant if there is neither an economically or technologically feasible MCL, nor an accurate way to measure the contaminant in water.

States generally obtain primary authority to implement the SDWA after proving to the EPA that they will adopt and enforce standards at least as stringent as the national standards. While the states may oversee the program, the public water systems themselves physically ensure the safety of the tap water through treatment, testing, and reporting. In addition to these "at the tap" protections, the SDWA requires states and public water suppliers to protect initial water sources from contamination. In particular, the SDWA provides for an Underground Injection Control (UIC) program to prevent contamination of underground water sources by underground injection of contaminated fluids.

Due to criticism that the original act was an inflexible, unfunded mandate with an unattainable regulatory schedule, the 104th Congress extensively amended the act in 1996 (P.L. 104-182, 110 Stat. 1613). These amendments included new pollution prevention approaches, public information requirements, added flexibility to the regulatory process, and a Drinking Water State Revolving Fund. Pollution prevention took the form primarily of source-water quality assessment programs to determine the current health of water supplies and delineate the area to be protected. In addition, public water suppliers were required to inform their year-round customers about the source and quality of their tap water with an annual consumer confidence report.

The most important element of the amendments was the critically necessary funding mechanism added to the SDWA's stringent water quality requirements. This fund provided federal monetary aid to public water systems to repair and upgrade their facilities, focusing particularly on assisting small and disadvantaged communities that might otherwise find these repairs too expensive. The fund also gave priority to programs using pollution prevention to safeguard their drinking water supply.

See also: FEDERAL WATER POLLUTIOIN CONTROL ACT.