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Safe Drinking Water Act of 1974

Last Updated: 2018

The problem of water pollution became a public concern in 1969, when the polluted Cuyahoga River, flowing through Cleveland, Ohio, caught fire. The Safe Drinking Water Act (SDWA) is the main federal law that ensures the quality of Americans’ drinking water. Passed in 1974, the SDWA protects public health by regulating all public water systems that serve at least twenty-five people, which totals over 151,000 systems in the United States. The SDWA’s regulations and water quality standards guard against threats to drinking water from improper disposal of chemicals, animal waste, human waste, pesticides, and naturally occurring substances.

The SDWA delegates most of the power to the U.S. Environmental Protection Agency (EPA), which in turn sets the national rules that states, municipal water systems, and private companies must follow. The EPA forms its standards based on health risks that are determined by what levels of certain contaminants could affect the entire population and how frequently they occur in U.S. waterways. Then, the health risks that certain levels of certain contaminants pose are calculated and a legal limit is established. The legal limit falls well below the amount shown to be hazardous in order to provide a margin of safety in case of water system neglect causing a rise in the containment.

A state can apply for “primacy,” which enables them to implement the SDWA within their own jurisdiction as long as they have proof that they will maintain the same, if not stricter, standards than the EPA. Maintaining primacy means that the states act as the primary agent for water delivery and must make sure water systems test for contaminants, review plans for water system improvements, conduct on-site inspections and sanitary surveys, provide training and technical assistance, and take action against water systems not meeting water quality standards.

All states except Wyoming and the District of Columbia have primacy. Wyoming’s legislature originally declined primacy under the premise that it was unfair for the state to use its own money to enforce regulations set at the federal level.

Public water systems are legally responsible for ensuring that contaminants stay below or do not exceed federal and state standards. In principle, water systems must treat the water and frequently test for contaminants that they must then report to the state. States are responsible for monitoring local compliance. If the water system is not meeting these standards, then it is their obligation to notify customers. The citizen advisory committees, rate boards, volunteers, and civic leaders who actively provide information and help protect water sources are an integral part of the maintenance of water systems. In practice, as the recent case of Flint, Michigan, made plain, responsible parties do not always behave responsibly.

Congress amended the SDWA in 1996, requiring states to have annual Consumer Confidence Reports, Source Water Assessment Programs, and Operator Certifications. This amendment also provides for a revolving Drinking Water State Fund, Cost-Benefit Analysis, and Public Information and Consultation, along with the establishment of the Microbial Contaminants and Disaffection Byproducts Board and a special fund for small water systems. In 2005, amendments exempted hydraulic fracking; 2015 amendments provided technical assistance to small public water systems, and 2016 amendments expanded the infrastructure public-private load program .

Implementation of the SDWA creates some tension between the federal and state governments over enforcement and funding issues. States with primacy must take responsibility for all public water systems within their borders. States are responsible for the day-to-day operations of the programs, including conducting inspections of the water systems and directing and financing state water regulatory programs. Additionally, states are required to maintain proper documentation of water testing and report those findings back to the EPA.

The national standards for drinking water are legally enforceable, which allows the EPA and the state to take action against careless water systems. This enforcement can range from administrative orders to fines and can have serious legal repercussions. The EPA can take action against the state, not just the water system, if one water system within the state is not in compliance with SDWA standards.

The consequences of a misguided decision can be devastating. This was dramatically evident in 2014 when financially strapped Flint, Michigan, in a cost-saving measure switched the city’s water source from Lake Huron water (purchased from Detroit) to the Flint River without adding the necessary corrosion control chemicals. The corrosive water removed a protective coating in the pipes, causing lead to leach into the water. The water became so tainted that Flint switched back to Lake Huron water in October 2015 and introduced corrective measures to rebuild pipe linings, but according to University of Michigan experts, even after initial cleanup 29,100 Flint residences had lines that need to be replaced. The city created the FAST Start program to remove and replace service lines leading to homes, but water quality improvements, lead pipe replacements, and other costs (included huge supplies of bottled water) cost federal and state governments hundreds of millions of dollars.

The SDWA has been criticized as an unfunded or underfunded federal mandate that places a significant financial burden on the states. Although the SDWA allows the EPA to fund up to 75 percent of the administration costs for states with primacy, historically, states fund 65 percent of the costs while the EPA only funds 35 percent.

Many states experience funding shortfalls in implementing SDWA’s regulations. The Association of State Drinking Water Administrators estimated an FY2013 funding gap in comprehensive state programs from all sources of $308 million between available resources of $440 and needed resources of $748 million.

The SDWA has also been criticized for the policy’s “one-size-fits-all” approach. The EPA set up the SDWA to regulate the same contaminants throughout the entire country, regardless of the location of the water supply and the local environment. Consequently, states’ already-tight budgets and inadequately staffed state water programs must monitor and test for contaminants that do not naturally occur in their area. Furthermore, the one-size-fits-all approach may ignore potentially hazardous water pollutants found only in one public water supply, but not included in the list of ninety contaminants.

SDWA is an example of cooperative federalism at work. The federal government sets national standards, 49 states have legal primacy of implementation, many local government entities own and operate public water systems. Together, these governments have reduced the health risks from tap water. Critics argue that this system can too easily abide abdication as well as sharing of responsibility. The implementation difficulties are accepted by a public that supports the policy goal of insuring safe drinking water.

SEE ALSO: Cooperative FederalismEnvironmental Policy


Association of State Drinking Water Administrators, Insufficient Resources for State Drinking Water Programs Threaten Public Health (December 2013); Denise Scheberle, Federalism and Environmental Policy (Washington, DC: Georgetown University Press, 1997); V. A. Sikora, “Water, Water, Everywhere,” Journal of Environmental Health 64 (May 2002): 37; B. Swichtenberg, “Landmark Legislation: The Clean Water and Safe Drinking Water Acts,” Water Engineering & Management 150 (February 2003): 19; and M. Tiemann, “Safe Drinking Water Act,” CRS Report for Congress, June 4, 1997, (accessed November 14, 2003).