Safe Drinking Water Act

National Primary Drinking Water Regulations

The SDWA requires EPA to establish National Primary Drinking Water Regulations (NPDWRs) for contaminants that may cause adverse public health effects.

The regulations include both mandatory levels (Maximum Contaminant Levels, or MCLs) and nonenforceable health goals (Maximum Contaminant Level Goals, or MCLGs) for each included contaminant. MCLs have additional significance because they can be used under the Superfund law as "Applicable or Relevant and Appropriate Requirements" in cleanups of contaminated sites on the National Priorities List.

Federal drinking water standards are organized into six groups:

Microorganisms

Disinfectants

Disinfection Byproducts

Inorganic Chemicals

Organic Chemicals

Radionuclides.

Microorganisms

EPA has issued standards for Cryptosporidium, Giardia lamblia, Legionella, coliform bacteria and enteric viruses. EPA also requires two microorganism-related tests to indicate water quality: plate count and turbidity.

Disinfectants

EPA has issued standards for chlorine, chloramine and chlorine dioxide.

Disinfection by-products

EPA has issued standards for bromate, chlorite, haloacetic acids and trihalomethanes.

Inorganic Chemicals

EPA has issued standards for antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, copper, cyanide, fluoride, lead, mercury, nitrate, nitrite, selenium and thallium.

"Lead Free" plumbing requirements

The 1986 amendments require EPA to set standards limiting the concentration of lead in public water systems, and defines "lead free" pipes as:

(1) solders and flux containing not more than 0.2 percent lead; (2) pipes and pipe fittings containing not more than 8.0 percent lead; and (3) plumbing fittings and fixtures as defined in industry-developed voluntary standards (issued no later than August 6, 1997), or standards developed by EPA in lieu of voluntary standards.

EPA issued an initial lead and copper regulation in 1991 and last revised the regulation in 2007.

Congress tightened the definition of "lead free" plumbing in a 2011 amendment to the Act.

EPA published a white paper in 2016 discussing options for additional revisions to the Lead and Copper Rule.

Organic Chemicals

EPA has issued standards for 53 organic compounds, including benzene, dioxin (2,3,7,8-TCDD), PCBs, styrene, toluene, vinyl chloride and several pesticides.

Radionuclides

EPA has issued standards for alpha particles, beta particles and photon emitters, radium and uranium.

Non-community water systems

Future NPDWR standards will apply to non-transient non-community water systems because of concern for the long-term exposure of a stable population. It is important to note that EPA's decision to apply future NPDWRs to non-transient non-community water systems may have a significant impact on Department of Energy facilities that operate their own drinking water systems.

Unregulated contaminants

The SDWA requires EPA to identify and list unregulated contaminants which may require regulation. The Agency must publish this list, called the "Contaminant Candidate List," every five years. EPA is required to decide whether to regulate at least five or more listed contaminants. EPA uses this list to prioritize research and data collection efforts, which support the regulatory determination process.

Monitoring, compliance and enforcement

Public water systems are required to regularly monitor their water for contaminants. Water samples must be analyzed using EPA-approved testing methods, by laboratories that are certified by EPA or a state agency.

A PWS must notify its customers when it violates drinking water regulations or is providing drinking water that may pose a health risk. Such notifications are provided either immediately, as soon as possible (but within 30 days of the violation) or annually, depending on the health risk associated with the violation. Community water systems—those systems that serve the same people throughout the year—must provide an annual "Consumer Confidence Report" to customers. The report identifies contaminants, if any, in the drinking water and explains the potential health impacts.

Oversight of public water systems is managed by "primacy" agencies, which are either state government agencies, Indian tribes or EPA regional offices. All state and territories, except Wyoming and the District of Columbia, have received primacy approval from EPA, to supervise the PWS in their respective jurisdictions. A PWS is required to submit periodic monitoring reports to its primacy agency. Violations of SDWA requirements are enforced initially through a primacy agency's notification to the PWS, and if necessary following up with formal orders and fines.

Airline water supplies

In 2004, EPA tested drinking water quality on commercial aircraft and found that 15 percent of tested aircraft water systems tested positive for total coliform bacteria. EPA published a final regulation for aircraft public water systems in 2009. The regulation requires air carriers operating in the U.S. to conduct coliform sampling, management practices, corrective action, public notification, operator training, and reporting and recordkeeping. An airline with a non-complying aircraft must restrict public access to the on-board water system for a specified period.

Underground Injection Control (UIC) Program

The 1974 act authorized EPA to regulate injection wells in order to protect underground sources of drinking water. The UIC permit system is organized into six classes of wells.

Class I. Industrial waste (hazardous and non-hazardous) and municipal wastewater disposal wells

Class II. Oil and gas related injection wells (except wells solely used for production; see Hydaulic fracturing exemption)

Class III. Solution mining wells

Class IV. Shallow hazardous and radioactive waste injection wells (no longer permitted)

Class V. Wells that inject non-hazardous fluids into or above underground sources of drinking water

Class VI. Geologic sequestration wells for carbon dioxide.

Hydaulic fracturing exemption

Congress amended the SDWA in 2005 to exclude hydraulic fracturing, an industrial process for recovering oil and natural gas, from coverage under the UIC program, except where diesel fuels are used. This exclusion has been called the "Halliburton Loophole". Halliburton is the world's largest provider of hydraulic fracturing services. The measure was a response to a recommendation from the Energy Task Force, chaired by Vice President Dick Cheney in 2001. (Cheney had been Chairman and CEO of Halliburton from 1995 to 2000.)

Whistleblower protection

The SDWA includes a whistleblower protection provision. Employees in the US who believe they were fired or suffered another adverse action related to enforcement of this law have 30 days to file a written complaint with the Occupational Safety and Health Administration.

Prelude

Prior to the SDWA there were few national enforceable requirements for drinking water. Improvements in testing were allowing the detection of smaller concentrations of contaminant and allowing more tests to be run.

Under state programs, some water works managers mistakenly believed that the major, real threats were behind them and their primary focus was on providing consistent and effective service through aging infrastructure, with major efforts at maintaining the bacteriological quality of drinking water.

1974 Act

The Safe Drinking Water Act was one of several pieces of environmental legislation in the 1970s. Discovery of organic contamination in public drinking water and the lack of enforceable, national standards persuaded Congress to take action.

Historically, up through 1914, drinking water quality in the United States was managed at the state and local level. After that, interstate waters were protected using United States Public Health Service (USPHS) standards. Ultimately the USPHS standards were adopted and expanded as national drinking water standards after passage of the 1974 law.

The 1974 law very clearly defined roles and responsibilities, giving EPA the job of generating scientifically based standards that would be applicable to all water supplies that served 25 or more customers and creating a process for setting new standards. EPA was mandated to contract with the National Academy of Sciences for a major study of contaminants in drinking water that might have health significance and to issue revised regulations once the NAS report was completed.

1986 amendments

The 1986 SDWA amendments required EPA to apply future NPDWRs to both community and non-transient non-community water systems when it evaluated and revised current regulations. The first case in which this was applied was the "Phase I" final rule, published on July 8, 1987. At that time NPDWRs were promulgated for certain synthetic volatile organic compounds and applied to non-transient non-community water systems as well as community water systems. This rulemaking also clarified that non-transient non-community water systems were not subject to MCLs that were promulgated before July 8, 1987. The 1986 amendments were signed into law by President Ronald Reagan on June 19, 1986.

In addition to requiring more contaminants to be regulated, the 1986 amendments included:

Well head protection

New monitoring for certain substances

Filtration for certain surface water systems

Disinfection for certain groundwater systems

Restriction on lead in solder and plumbing

More enforcement powers.

1996 SDWA amendments

In 1996, Congress amended the Safe Drinking Water Act to emphasize sound science and risk-based standard setting, small water supply system flexibility and technical assistance, community-empowered source water assessment and protection, public right-to-know, and water system infrastructure assistance through a multibillion-dollar state revolving loan fund. The amendments were signed into law by President Bill Clinton on August 6, 1996.

Main points of the 1996 amendments

1. Consumer Confidence Reports: All community water systems must prepare and distribute annual reports about the water they provide, including information on detected contaminants, possible health effects, and the water's source.
2. Cost-Benefit Analysis: EPA must conduct a thorough cost-benefit analysis for every new standard to determine whether the benefits of a drinking water standard justify the costs.
3. Drinking Water State Revolving Fund. States can use this fund to help water systems make infrastructure or management improvements or to help systems assess and protect their source water.
4. Microbial Contaminants and Disinfection Byproducts: EPA is required to strengthen protection for microbial contaminants, including cryptosporidium, while strengthening control over the byproducts of chemical disinfection. EPA promulgated the Stage 1 Disinfectants and Disinfection Byproducts Rule and the Interim Enhanced Surface Water Treatment Rule to address these risks.
5. Operator Certification: Water system operators must be certified to ensure that systems are operated safely. EPA issued guidelines in 1999 specifying minimum standards for the certification and recertification of the operators of community and non-transient, noncommunity water systems. These guidelines apply to state operator certification programs. All states are currently implementing EPA-approved operator certification programs.
6. Public Information and Consultation: SDWA emphasizes that consumers have a right to know what is in their drinking water, where it comes from, how it is treated, and how to help protect it. EPA distributes public information materials (through its Drinking Water Hotline, Safewater web site, and Resource Center) and holds public meetings, working with states, tribes, water systems, and environmental and civic groups, to encourage public involvement.
7. Small Water Systems: Small water systems are given special consideration and resources under SDWA, to make sure they have the managerial, financial, and technical ability to comply with drinking water standards.

2005 amendment

Through the Energy Policy Act of 2005, the Safe Drinking Water Act was amended to exclude the underground injection of any fluids or propping agents other than diesel fuels used in hydraulic fracturing operations from being considered as "underground injections" for the purposes of the law.

2011 amendment

Congress passed the Reduction of Lead in Drinking Water Act in 2011. This amendment, effective in 2014, tightened the definition of "lead-free" plumbing fixtures and fittings.

2015 amendments

The Drinking Water Protection Act was enacted on August 7, 2015. It required EPA to submit to Congress a strategic plan for assessing and managing risks associated with algal toxins in drinking water provided by public water systems. EPA submitted the plan to Congress in November 2015.

The Grassroots Rural and Small Community Water Systems Assistance Act was signed by President Barack Obama on December 11, 2015. The amendment provides technical assistance to small public water systems, to help them comply with National Primary Drinking Water Regulations.