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Regulatory Information by Topic: Water

EPA enforces federal clean water and safe drinking water laws, provides support for municipal wastewater treatment plants, and takes part in pollution prevention efforts aimed at protecting watersheds and sources of drinking water.

On this page:

Animal Feeding Operations

See: Cross-Cutting Issues: Animal Feeding Operations

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Biosolids

Biosolids are the nutrient-rich organic materials resulting from the treatment of sewage sludge. Only biosolids that meet the most stringent standards spelled out in federal and state rules can be approved for use as a fertilizer.

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Drinking Water

The Safe Drinking Water Act (SDWA) is the main federal law that ensures the quality of Americans' drinking water. Under SDWA, EPA sets standards for drinking water quality and oversees the states, localities, and water suppliers who implement those standards.

Read more here About the Safe Drinking Water Act.

Laws and Regulations

Compliance

Enforcement

Policy and Guidance

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Ground Water

Many communities obtain their drinking water from aquifers. Unfortunately, the ground water can become contaminated by human activity. These chemicals can enter the soil and rock, polluting the aquifer and eventually the well.

Laws and Regulations

  • Ground Water Rule: provides for increased protection against microbial pathogens in public water systems that use ground water sources.
  • Underground Injection Control Program: responsible for regulating the construction, operation, permitting and closure of injection wells that place fluids underground for storage or disposal.
  • Source Water Protection: ensuring the quality of drinking water by protecting it from the source to the tap.

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Hydraulic Fracturing

See: Natural Gas Extraction: Hydraulic Fracturing

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Impaired Waters

Under Section 303 D of the Clean Water Act (CWA), states, territories and authorized tribes are required to develop lists of impaired waters. These are waters that are too polluted or otherwise degraded to meet the water quality standards set by states, territories, or authorized tribes.

Laws and Regulations

Policy and Guidance

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Mercury

See Cross-Cutting Issues: Mercury.

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Mountaintop Mining

See Surface Coal Mining in Appalachia

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Oceans and Coastal Waters

Laws and Regulations

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Surface Coal Mining in Appalachia

Mining operations are regulated under the Clean Water Act (CWA), including discharges of pollutants to streams from valley fills (CWA Section 402) and the valley fill itself where the rock and dirt is placed in streams and wetlands (CWA Section 404). Coal mining operations are also regulated by the Department of Interior's Office of Surface Mining Reclamation and Enforcement.

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Surface Water: Lakes, Rivers, and Streams

  • Surface Water Standards and Guidance: including water quality standards, water quality criteria under CWA Section 304(a)(1), and cooling water intake structures under CWA Section 316(b).

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Stormwater

EPA controls storm water and sewer overflow discharges through the National Pollutant Discharge Elimination System (NPDES). NPDES provides guidance to municipalities and state and federal permitting authorities on how to meet stormwater pollution control goals as flexibly and cost-effectively as possible.

Laws and Regulations

Compliance

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Wastewater

EPA regulates the discharge and treatment of wastewater under the Clean Water Act (CWA). The National Pollutant Discharge Elimination System (NPDES) issues permits to all wastewater dischargers and treatment facilities. These permits establish specific discharge limits, monitoring and reporting requirements and may also require these facilities to undertake special measures to protect the environment from harmful pollutants.

Laws and Regulations

Compliance

See also: Animal Feeding Operations.

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Watersheds

Laws and Regulations

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Wetlands

Laws and Regulations

Compliance

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