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Clean Water Act (CWA)

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The objective of the Federal Water Pollution Control Act, commonly referred to as the Clean Water Act (CWA), is to restore and maintain the chemical, physical, and biological integrity of the nation's waters by preventing point and nonpoint pollution sources, providing assistance to publicly owned treatment works for the improvement of  wastewater treatment, and maintaining the integrity of wetlands.  

Summary of the Clean Water Act

Agriculture-Specific Requirements

More Information

Related topics
Land Use
Surface and Groundwater

Related publications from the Ag Center
Aquaculture
Agricultural Animals
Water
Watershed
Wetlands

Text of law and related regulations
Clean Water Act Full Text
Water Regulation: 40 CFR Part 100 - 149 (Parts 100-135; Parts 136-149)

More information from states
National Association of State Departments of Agriculture (NASDA) Exit EPA
EZregs Exit EPA - University of Illinois Extension Web site that identifies environmental regulations that pertain to specific agricultural and horticultural operations and practices in Illinois.

Clean Water Act compliance and enforcement
Clean Water Act: Agriculture-Related Enforcement Cases
Water Enforcement Division
Water Enforcement Bulletin
Water Enforcement Policies and Guidance
Multimedia Enforcement Division
Protocol for Conducting Environmental Compliance Audits for Municipal Facilities under EPA’s Wastewater Regulations (PDF) (126 pp, 775K)

Clean Water Act Training
EPA CWA online training
Tribal Training Web site

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Overview of Clean Water Act

Pollutants regulated under the CWA include "priority" pollutants, including various toxic pollutants; "conventional" pollutants, such as biochemical oxygen demand (BOD), total suspended solids (TSS), fecal coliform, oil and grease, and pH; and "non-conventional" pollutants, including any pollutant not identified as either conventional or priority. The CWA regulates both direct and indirect discharges.

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National Pollutant Discharge Elimination System

The National Pollutant Discharge Elimination System (NPDES) program - Clean Water Act Section 402 (PDF) Exit EPA(scroll down to Section 402) (234 pp, 571K) - controls direct discharges into navigable waters. Direct discharges or "point source" discharges are from sources such as pipes and sewers. NPDES permits, issued by either EPA or an authorized state/tribe contain industry-specific, technology-based and/or water-quality-based limits, and establish pollutant monitoring and reporting requirements. (EPA has authorized 40 states to administer the NPDES program.) A facility that intends to discharge into the nation's waters must obtain a permit before initiating a discharge. A permit applicant must provide quantitative analytical data identifying the types of pollutants present in the facility's effluent. The permit will then set forth the conditions and effluent limitations under which a facility may make a discharge.

An NPDES permit may also include discharge limits based on federal or state/tribe water quality criteria or standards that were designed to protect designated uses of surface waters, such as supporting aquatic life or recreation. These standards, unlike the technological standards, generally do not take into account technological feasibility or costs. Water quality criteria and standards vary from state to state (tribe to tribe) and site to site, depending on the use classification of the receiving body of water. Most states/tribes follow EPA guidelines that propose aquatic life and human health criteria for many of the 126 priority pollutants.

More information from EPA
NPDES Compliance Monitoring Strategy for the Core Program and Wet Weather Sources (PDF) (28 pp, 367K) - Provides inspection frequency goals for the core NPDES program and for wet weather sources including Combined Sewer Overflows (CSO), Sanitary Sewer Overflows (SSO), Concentrated Animal Feeding Operations (CAFO), and Storm Water.

Aquaculture Project
Discharges into an aquaculture project require a National Pollutant Discharge Elimination System (NPDES) permit. Aquaculture means a "defined managed water area which uses discharges of pollutants into that designated area for the maintenance or production of harvestable freshwater estuarine or marine plants or animals."

Related Sectors
Aquaculture Operations

Related publications from the Ag Center
Aquaculture

Related environmental requirements
Clean Water Act Section 402 (PDF) (scroll down to Section 402) (234 pp, 571K)Exit EPA
40 CFR Part 122.25 Exit EPA

More information from EPA
National Pollutant Discharge Elimination System Permit Program
Effluent Guidelines for the Aquatic Animal Production Industry
NPDES Voluntary Permit Fee Incentives

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Concentrated Aquatic Animal Production Facilities
Concentrated aquatic feeding operations are direct dischargers and require an NPDES permit if they annually meet the following general conditions: (1) produce more than 9,090 harvest weight kilograms (about 20,000 pounds) of cold water fish (e.g., trout, salmon); or (2) produce more than 45,454 harvest weight kilograms (about 100,000 pounds) of warm water fish (e.g., catfish, sunfish, minnows).

Related Sectors
Aquaculture Operations

Related publications from the Ag Center
Aquaculture

Related environmental requirements
Clean Water Act Section 402 (PDF) (scroll down to Section 402) (234 pp, 571K)Exit EPA
40 CFR Part 122.24 Exit EPA

More information from EPA
National Pollutant Discharge Elimination System Permit Program
Effluent Guidelines for the Aquatic Animal Production Industry

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Storm Water Discharges

In 1987 the CWA was amended to require EPA to establish a program to address storm water discharges. In response, EPA promulgated the NPDES storm water permit application regulations. Storm water discharge associated with industrial activity means the discharge from any conveyance which is used for collecting and conveying storm water and which is directly related to manufacturing, processing, or raw materials storage areas at an industrial plant (40 CFR 122.26 Exit EPA). These regulations require that facilities with the following storm water discharges apply for an NPDES permit: (1) a discharge associated with industrial activity; (2) a discharge from a large or medium municipal storm sewer system; or (3) a discharge which EPA or the state/tribe determines to contribute to a violation of a water quality standard or which is a significant contributor of pollutants to waters of the United States.

The term "storm water discharge associated with industrial activity" means a storm water discharge from one of 11 categories of industrial activity defined in 40 CFR Part 122.26. Exit EPA  Six of the categories are defined by SIC codes, while the other five are identified through narrative descriptions of the regulated industrial activity. If the primary SIC code of the facility is one of those identified in the regulations, the facility is subject to the storm water permit application requirements. If any activity at a facility is covered by one of the five narrative categories, storm water discharges from those areas where the activities occur are subject to storm water discharge permit application requirements.

As part of storm water permits, facilities are often required to implement pollution prevention plans. This reflects EPA’s commitment to preventing pollution at the source, before it causes environmental problems that cost the public and private sectors in terms of lost resources and funding to correct or remediate environmental damages.

Storm water pollution prevention plans must be prepared in accordance with good engineering practices. The plan should identify potential sources of pollution that may reasonably be expected to affect the quality of storm water discharges associated with industrial activity from the facility. The plan should also describe and ensure the implementation of practices that reduce the pollutants in storm water discharges.

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Pretreatment Program

Another type of discharge that is regulated by the CWA is discharge that goes to a publicly owned treatment works (POTW). The national pretreatment program (CWA Section 307(b)) controls the indirect discharge of pollutants to POTWs by "industrial users." Facilities regulated under Section 307(b) must meet certain pretreatment standards. The goal of the pretreatment program is to protect municipal wastewater treatment plants from damage that may occur when hazardous, toxic, or other wastes are discharged into a sewer system and to protect the quality of sludge generated by these plants. Discharges to a POTW are regulated primarily by the POTW itself, rather than the state/tribe or EPA.

EPA has developed general pretreatment standards and technology-based standards for industrial users of POTWs in many industrial categories. Different standards may apply to existing and new sources within each category. "Categorical" pretreatment standards applicable to an industry on a nationwide basis are developed by EPA. In addition, another kind of pretreatment standard, "local limits," are developed by the POTW to help the POTW achieve the effluent limitations in its NPDES permit.

Regardless of whether a state/tribe is authorized to implement either the NPDES or the pretreatment program, if it develops its own program, it may enforce requirements more stringent than federal standards.

Related environmental requirements
Clean Water Act Section 1317 Exit EPA
40 CFR Part 403

More information from EPA
National Pretreatment Program

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Biosolids Program

Biosolids are the treated residuals from wastewater treatment that can be used beneficially. Wastewater residuals (formerly sewage sludge) are not referred to as biosolids unless they have been treated so that they can be beneficially used.

Biosolids and Agriculture
EPA's biosolids rule governs the land application of  residuals from wastewater treatment. The risk assessment for the rule that governs the land application of biosolids took nearly 10 years to complete and had extensive rigorous review and comment. The risk assessment evaluated and established limits for a number of pollutants.  In the process of establishing these limits, EPA compared the relevant toxic's exposure data, which was obtained from a cross section of representative studies, to the appropriate oral reference dose (RfD) and human cancer potency (Q1*) values, (i.e., the allowable dose of each pollutant.). These exposures were evaluated via 14 pathways of exposure with the most limiting pathway being chosen as the limit. In spite of all the safety factors and uncertainty factors built into the process, environmental and human health risks were found to be very low.

Related topics
Nutrient Management and Fertilizer

Related publications from the Ag Center
Nutrient Management and Fertilizer

Related environmental requirements 
Clean Water Act by Section Exit EPA
40 CFR Part 503
A Plain English Guide to the EPA Part 503 Biosolids Rule

More information from EPA 
Biosolids
Biosolids -- Frequently Asked Questions

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Nonpoint Source Pollution

Nonpoint source (NPS) pollution, unlike pollution from industrial and sewage treatment plants, comes from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters, and even underground sources of drinking water.

These pollutants include:

Nonpoint Source Pollution and Agriculture
Through a variety of programs (including, as appropriate, non-regulatory or regulatory programs), states assist and encourage producers to use best management practices to reduce or prevent instances of  nonpoint source pollutants migrating into waters. States manage the  nonpoint source program on a watershed-by-watershed basis whenever possible.

Related publications from the Ag Center
Surface and Groundwater
Water

Related topics
Surface and Groundwater

Related environmental requirements
Clean Water Act Section 319
Applying for and Administering CWA Section 319 Grants: A Guide for State Nonpoint Source Agencies

More information from EPA
Nonpoint Source Pollution Control Program
State-EPA NPS Partnership
 Forestry Best Management Practices in Watersheds
Fact Sheet on Protecting Water Quality from Agricultural Runoff

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National Estuary Program

The National Estuary Program (NEP) was established in 1987 by amendments to the Clean Water Act to identify, restore, and protect nationally significant estuaries of the United States. Unlike traditional regulatory approaches to environmental protection, the NEP targets a broad range of issues and engages local communities in the process. The program focuses not just on improving water quality in an estuary, but on maintaining the integrity of the whole system -- its chemical, physical, and biological properties, as well as its economic, recreational, and aesthetic values.

The National Estuary Program is designed to encourage local communities to take responsibility for managing their own estuaries. Each NEP is made up of representatives from federal, state, and local government agencies responsible for managing the estuary's resources, as well as members of the community -- citizens, business leaders, educators, and researchers. These stakeholders work together to identify problems in the estuary, develop specific actions to address those problems, and create and implement a formal management plan to restore and protect the estuary.

Estuaries and Agriculture
Farms or farm organizations within a study area of one of the designated "estuaries of national significance" are encouraged to join a local management conference with other stakeholders to identify major environmental problems and needed remedies to those problems. Through a consensus-based process, all stakeholders work together to develop a plan of action according to needs of their own communities.

Related environmental requirements
Clean Water Act Section 320

More information from EPA
National Estuary Program
"Indicator Development for Estuaries" Manual

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National Coastal Water Program

The program includes the Chesapeake Bay Program, Great Lakes Program, and Gulf of Mexico Program. The mission of the Chesapeake Bay Program is to lead and empower others to protect and restore the Chesapeake Bay ecosystem for future generations.  The Great Lakes National Program Office (GLNPO) brings together federal, state, tribal, local, and industry partners in an integrated, ecosystem approach to protect, maintain, and restore the chemical, biological, and physical integrity of the Great Lakes. The goal of the Gulf of Mexico Program is to protect, restore, and enhance the coastal and marine waters of the Gulf of Mexico and its coastal natural habitats, to sustain living resources, to protect human health and the food supply, and to ensure the recreational use of Gulf shores, beaches and waters -- in ways consistent with the economic well-being of the region.

National Coastal Water Program and Agriculture
Agricultural establishments and other agribusinesses located within program boundaries covered by the Chesapeake Bay, Great Lakes, and  Gulf of Mexico programs may have additional water-related requirements.

Related topics
Surface and Groundwater

Related publications from the Ag Center
Water

Related environmental requirements
Chesapeake Bay -- Clean Water Act Section 117 Exit EPA
Great Lakes - Clean Water Act Section 118 Exit EPA
Water Quality Guidance for the Great Lakes System
 Fact Sheet: Final Water Quality Guidance for the Great Lakes System
Water Quality Guidance for the Great Lakes System: Supplementary Information Document Section VIII. C., Total Maximum Daily Loads (PDF) (49 pp, 116K)

More information from EPA
Chesapeake Bay Program
Great Lakes Program
Gulf of Mexico Program 

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Oil Spill Prevention, Control, and Countermeasures (SPCC) Program

In 1973, EPA issued the Oil Pollution Prevention regulation to address the oil spill prevention provisions contained in the Clean Water Act of 1972. The regulation forms the basis of EPA's oil spill prevention, control, and countermeasures, or SPCC, program, which seeks to prevent oil spills from certain aboveground and underground storage tanks.

Final Action to Amend the Spill Prevention, Control, and Countermeasure (SPCC) Rule
In December 2006, EPA amended the SPCC rule to streamline some of its requirements.  As part of the Oil Pollution Prevention regulation, the SPCC rule outlines requirements for prevention of, preparedness for, and response to oil discharges.  Regulated facilities, including some farms, must develop and implement SPCC Plans that establish procedures and equipment requirements to help prevent oil discharges from reaching waters of the United States or adjoining shorelines.

What is a “farm” for purposes of the SPCC rule?

In the SPCC rule, EPA defines a farm as “a facility on a tract of land devoted to the production of crops or raising of animals, including fish, which produced and sold, or normally would have produced and sold, $1,000 or more of agricultural products during a year.”

What farms are subject to the SPCC rule?

The SPCC rule applies to owners or operators of farms that:

The following are exempt from the SPCC rule:

What are the compliance dates for farms?

In December 2006, EPA extended the compliance dates for preparing or amending, and implementing SPCC Plans for farms until the Agency promulgates a rule specifically addressing how farms should be regulated under the SPCC rule. During the extension, EPA will determine how to better tailor and streamline the SPCC rule for farms. 

A farm starting operation…  Must...
On or before August 16, 2002*
  • Maintain its existing SPCC Plan based on the SPCC requirements prior to the new 2002 amendments 
  • Amend and implement the SPCC Plan when EPA promulgates a rule specific for farms and specifies a compliance date for farms
After August 16, 2002*
  • Prepare and implement an SPCC Plan when EPA promulgates a rule specific for farms and specifies a compliance date for farms

* August 16, 2002 is the date that the amended SPCC rule became effective.

Information for Farms about the December 2006 Revisions to SPCC Requirements

Related publications from the Ag Center
Emergency Planning and Response

Related topics
Tanks and Containment
Emergency Planning and Response
Upcoming and Recent Compliance Dates

Related environmental requirements
Clean Water Act Section 1321 Exit EPA
Oil Pollution Act Exit EPA
40 CFR Part 112

More information from EPA
 Oil Spill Program
EPA press release on the Final Rule on Oil Spill Prevention, Control, and Countermeasures
SPCC Rule Amendment: Animal Fats and Vegetable Oils Fact Sheet

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Total Maximum Daily Loads

Some waters in the nation still do not meet the Clean Water Act national goal of "fishable, swimmable" despite the fact that nationally required levels of pollution control technology have been implemented by many pollution sources. Clean Water Act Section 1313 Exit EPA addresses these waters that are not "fishable, swimmable" by requiring states to identify the waters and to develop total maximum daily loads (TMDLs) for them, with oversight from the U.S. Environmental Protection Agency. As such, TMDLs can play a key role in watershed management.

TMDLs and Agriculture
Each state must identify waters at risk and establish Total Daily Maximum Loads (TMDLs) to protect those waters. This includes identification of needed load reductions within a watershed from agricultural producers and other nonpoint sources. These load reductions are to be achieved through nonpoint source programs established under Clean Water Act Section 319 and Coastal Zone Act Reauthorization Amendment (CZARA) section 6217.

Related topics
Surface and Groundwater

Related publications from the Ag Center
Nutrient Management and Fertilizer
Water
Watershed

Related environmental requirements
Clean Water Act Section 303 Exit EPA
Clean Water Act Section 319
Coastal Zone Act Reauthorization Section 6217

More information from EPA
Total Maximum Daily Load Program
TMDL Guidance
Costs of the TMDL Program

More information from USDA
Evaluation of Sediment Transport Data for Clean Sediment TMDLs

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Wetlands

Section 404 of the Clean Water Act (CWA) establishes a program to regulate the discharge of dredged or fill material into waters of the United States, including wetlands. Activities in waters of the United States regulated under this program include fill for development, water resource projects (such as dams and levees), infrastructure development (such as highways and airports) and mining projects. Section 404 requires a permit before dredged or fill material may be discharged into waters of the United States, unless the activity is exempt from Section 404 regulation. Many normal farming practices are exempt from Section 404.

Wetlands and Agriculture
Section 404 of the Clean Water Act establishes a permit program to regulate the discharge of dredged or fill material into the waters of the U.S., including wetlands. Clean Water Act Section 404(f) exempts from regulation discharges associated with certain specified activities, provided the discharges do not convert an area of waters of the U.S. to a new use, and do not impair the flow or circulation of waters of the U.S. or reduce the reach of waters of the U.S. For example, a permit generally is not needed for discharges of dredged or fill material associated with normal farming, ranching, and forestry activities, such as plowing, cultivating, minor drainage, and harvesting for the production of food, fiber, and forest products or upland soil and water conservation practices. This exemption pertains to normal farming and harvesting activities that are part of established, ongoing farming or forestry operations.

Prior converted croplands are not waters of the U.S., and are exempt from regulation under Section 404 of the Clean Water Act. Prior converted croplands are also exempt from the wetland conservation (Swampbuster) provisions of the Food Security Act. USDA’s Natural Resources Conservation Service has the lead responsibility for identifying wetlands on agricultural lands for purposes of implementing USDA’s Swampbuster program. The Corps of Engineers has the lead for identifying wetlands on agricultural lands for purposes of determining Clean Water Act jurisdiction. (Jurisdictional determinations made by the Corps of Engineers for Clean Water Act purposes may not be valid for complying with Swampbuster; likewise, NRCS wetland determinations may not be valid for determining Clean Water Act jurisdiction on a particular site.)

Agricultural establishments and other agribusinesses should check with the local Corps office if they have questions regarding whether ongoing or planned activities in wetlands are regulated under the Clean Water Act section 404 program. They should also check with the Natural Resource Conservation Service (NRCS) before clearing, draining, or manipulating any wet areas to make sure their eligibility for farm benefits is maintained.

Related publications from the Ag Center
Wetlands

Related topics
Land Use -- Wetlands
Land Use -- Dredge and Fill Activities

Related environmental requirements
Wetlands Regulatory Authority Fact Sheet (PDF) (2 pp, 687K)
Clean Water Act Section 404 -- text
CWA Section 404 Regulations
40 CFR Parts 230-233 (PDF) (40 pp, 109K)
Policy and Technical Guidance Documents
Executive Orders

More information from EPA
Wetlands

More information from USDA
Natural Resources Conservation Service
Wetland Science Institute (WLI)

Telephone assistance from EPA
Wetlands Hotline: 800-832-7828

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