Summary of Environmental Law in the United States

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9 Protection and Management of Water Resources


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9.1 Establishing Water Discharge Standards


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Permits issued under the Clean Water Act (CWA) must ensure compliance with three general types of standards: technology-based standards, water quality-based standards, and, in the case of a small number of toxic compounds, health-based effluent standards.

Technology-based standards

The CWA employs three technology-based water pollution control standards. "Best practicable control technology currently available" (BPT) sets uniform, industry-wide effluent standards that approximate the average amount of control achieved from existing technology in the specific industry. BPT sets the initial national floor applicable to all existing industrial sources of water pollution. "Best available technology economically achievable" (BAT) applies primarily to certain toxic pollutants,33 U.S.C. sec. 1317, and non-conventional pollutants, 33 U.S.C. sec. 1311(b)(2)(F). "Best conventional pollutant control technology" (BCT) is the second level of control for conventional pollutants, including biochemical oxygen demand (BOD), total suspended solids (TSS), fecal coliform, and pH, and incorporates a stringent cost effectiveness tool. "Best available demonstrated control technology" (BACT) forms the basis for new source performance standards (NSPS). BACT incorporates the "greatest degree of effluent reduction achievable," which is set according to different categories of industrial and agricultural activities. 33 U.S.C. sec. 1316.

Water Quality-Based Standards

Permits must ensure compliance with any state water quality-based standards. States must classify all state waters according to specific uses and then set an ambient water quality standard to protect that use. Once the standard is set, limitations must be included to ensure that the standards are met. The federal role is limited to reviewing the standards or developing replacement standards for states that fail to meet minimum federal requirements. 33 U.S.C. sec. 1313; 40 C.F.R. pt. 131. The Environmental Protection Agency (EPA) also retains, but has rarely used, the authority to impose more stringent water quality limitations if necessary to meet the national goal of fishable and swimmable waters.

Health-Based Standards

Where the BAT standard is not sufficient to achieve an "ample margin of safety" in protecting the environment and public health from certain toxic pollutants, EPA has the authority to issue toxic pollutant effluent standards. 33 U.S.C. sec. 1317. In setting these standards, the agency does not consider economic factors. Toxic pollutant effluent standards have been set for six chemicals: aldrin, DDT and related compounds, endrin, toxaphene, benzidine, and polychlorinated biphenyls. 40 C.F.R. pt. 129.

State Standards

States have the explicit right to enact any water quality standard or limitation that is more stringent than those required by federal statute. 33 U.S.C. sec. 1370. Most states have enacted separate state water pollution control laws and regulations. The states also take the lead role in setting water quality-based standards, which form the basis for both federal National Pollutant Discharge Elimination System (NPDES) and state permits. States must also be given an opportunity to review any federal license before it is issued, which may result in any discharge into its navigable waters. The state can object to the license if its standard will not be complied with. 33 U.S.C. sec. 1342.

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9.2 Point Sources


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NPDES Permits

The Clean Water Act prohibits any person from discharging a pollutant from. a point source into navigable waters without a NPDES permit. 33 U.S.C. sec. 1342; 40 C.F.R. pt. 122. The NPDES permit is the regulatory tool for translating the general standards described in Section 9.1 into specific effluent limitations applicable to specific polluters. "Point source" is defined very broadly to include any "discernible, confined and discrete conveyance," including, for example, any pipe, ditch, channel, tunnel, conduit, well, or container from which pollutants are or may be discharged. "Navigable waters" have been defined to mean virtually every surface water body in the country that is or may be used in interstate or foreign commerce, including wetlands. 33 U.S.C. sec. 1362(7); 40 C.F.R. sec. 122.2.

Exceptions to NPDES

The definition of point source expressly excludes agricultural stormwater discharges or return flows from agriculture. 33 U.S.C. sec. 1362(14). Other exceptions to the requirements for a NPDES permit include: routine discharges from vessels; most discharges of dredged or fill material which are regulated under section 6406 of the CWA (see Section 9.7: Protection of Fresh Water Ecosystems); indirect discharges into publicly owned treatment works (POTW's) which are regulated for pretreatment standards; discharges in compliance with certain emergency response efforts; and, discharges into some privately owned treatment works. 40 C.F.R. sec. 122.3.

Publicly Owned Treatment Works and Municipal Waste

The NPDES permitting system only applies to direct discharges into navigable waters. Dischargers to POTW do not receive a NPDES permit. Such indirect industrial dischargers must still comply with pretreatment standards to prevent pollutants from interfering with the POTW's operations. 33 U.S.C. sec. 1317; 40 C.F.R. pt. 403. In states with approved NPDES programs, the state can choose to assume the responsibility for the local pretreatment program. 40 C.F.R. pt. 403.


Polluters can apply for a variance from any federal effluent guideline or standard if they demonstrate that there are fundamentally different economic or technical factors at the facility from those underlying EPA's effluent standards. 33 U.S.C. sec. 1311(n). Other variances are available for certain non-conventional pollutants, such as ammonia, chlorine, color, iron, and total phenols, if the discharger demonstrates that the discharge will not harm public water supplies, the propagation of fish and wildlife, or human health. 33 U.S.C. sec. 1311(g). In practice, this standard has been difficult to meet. A similar standard allows a variance from the BAT standard typically applicable to thermal pollution if a facility demonstrates that their proposed standard is more stringent than necessary to protect fish and wildlife. This variance is used primarily by cooling towers at power plants. 33 U.S.C. sec. 1326.

State Water Quality Permits

Every state also regulates water pollution within their territory. This sometimes results in a dual system of permitting, whereby each facility must obtain both a federal NPDES permit and a state discharge permit. States can also gain EPA approval of state permitting systems so the states themselves can administer the NPDES program. In such cases, one permit issued by the state government meets both the federal and state requirements. 33 U.S.C. sec. 1342(a)(5).

Rivers and Harbors Act

Pursuant to the Rivers and Harbor Act, the deposit of refuse in navigable waters is also prohibited unless a permit has been obtained from the Army Corps of Engineers. 33 U.S.C. sec. 407.

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9.3 Non-Point Sources


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See also Section 19: Agriculture; and, Section 15: Private Land Use Planning and Management.

Non-point sources of water pollution (e.g., agricultural or urban runoff) may be regulated under the CWA, the Coastal Zone Management Act (CZMA), or state programs.

Clean Water Act

The CWA requires each state to identify: those waters that cannot meet water quality standards without control of non-point sources; the categories of non-point sources that significantly pollute those waters; the methods used to determine best management practices (BMP's) for those categories of non-point sources; and, any existing programs aimed at curbing non-point pollution. 33 U.S.C. sec. 1329. Each state must also submit for EPA approval a state management program detailing how the state proposes to reduce non-point pollution through implementing the BMP's. 33 U.S.C. sec. 1329(b). Once EPA approves the assessment and program, the state is eligible for federal funding of up to 60 percent of the costs of implementing the program. 33 U.S.C. sec. 1329(h). EPA is authorized to complete the assessment and develop a management program for any state that does not do so. 33 U.S.C. sec. 1329(d)(3). In such states, local governments may be eligible for federal funds directly. 33 U.S.C. sec. 1329(e).

Coastal Zone Management Act

Under the CZMA, states that want to continue to receive full federal funding for their coastal zone management programs must adopt a coastal non-point source pollution control program. The programs are intended to encourage land use practices and better management of critical coastal areas to stop degradation of coastal waters. 16 U.S.C. sec. 1455b. For more information, see Section 10.1: Coastal Management and Land Use Restrictions.

State Programs

In addition to meeting the federal mandate, several states have adopted their own programs for reducing urban and/or agricultural runoff.

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9.4 Protection of Safe Drinking Water


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See also Section 19: Agriculture.

The federal Safe Drinking Water Act (SDWA) was enacted in 1974 and amended in 1986 and 1996. The SDWA requires all public water systems to meet certain national primary drinking water regulations. 42 U.S.C. secs. 300f to 300j-36. EPA must set health-based standards, called maximum contaminant level goals (MCLGs), for chemicals that "are known or anticipated to occur" in public water supplies and maximum contaminant level (MCL) regulations which are as close to achieving the MCLGs as is economically or technically feasible, using the best available technology or practices. 42 U.S.C. sec. 300g-1. Substantially reformed in 1996, Pub. L. No. 182, 110 Stat.1613, the SDWA requires that by 2001, and every five years after that, EPA must decide whether or not to regulate at least five of the contaminants listed in the legislation. The aim is to regulate the contaminants that pose the greatest risk to public health as determined by using risk assessment and cost-benefit analysis. Once a contaminant is identified as requiring regulation, EPA must propose, within two years, a maximum contaminant level goal (MCLG) and national primary drinking water regulation which must become effective within eighteen months. Public water systems are required to meet the MCL regulation. The SDWA also created a program for eliminating lead from water coolers in schools and other buildings. 42 U.S.C. secs. 300j-21 to 300j-26.


Almost every state and territory is authorized to administer the SDWA. 42 U.S.C. sec. 300g-2. Any authorized state may issue variances from the national primary drinking water regulations if the background levels of water entering the public water system makes it impossible to meet the national primary drinking water regulations and the supplier has employed the best available technology. The state can also exempt any public water system from the national regulations for any compelling factors, including economic factors. In such a case, the state must establish a compliance schedule for the public water system, 42 U.S.C. sec. 300g-4(a).

State Revolving Fund

The 1996 SDWA amendments established a state revolving fund (SRF) to make funds available to states and water systems in order to promote the health protection objectives of the SDWA. Funds, provided in the form of grants and low interest loans, are to be used for infrastructure improvements, source water protection, capacity development, and operator certification programs. To become eligible for SRF, states must qualify by meeting 14 criteria established by the EPA, including using the funds in accordance with an "intended use plan" and providing EPA with a biennial report and annual audit. EPA can withhold funds from states that have not developed and implemented the appropriate capacity development programs. In an effort to provide substantial flexibility on the part of the states in developing and implementing programs, federal requirements are minimal.

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9.5 Protection of Groundwater


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See also Section 15: Private Land Use Planning and Management; and, Section 16: Environmental Management of Public Lands.

Federal statutes protecting groundwater resources include the SDWA, RCRA, and CERCLA. The SDWA program covers underground injection and wellhead protection, and establishes a state ground water protection program authorizing the EPA to provide grants to States to develop programs to promote protection of groundwater resources.

Underground Injection Control

Under the SDWA, EPA has prohibited any unauthorized underground injection. 40 C.F.R. sec. 144.11. EPA requires states to prepare an underground injection control program, particularly to protect underground drinking water supplies. 42 U.S.C. secs. 300h to 300h-7; 40 C.F.R. pts. 144-148. There is a special program regulating hazardous waste injection under the Resource Conservation and Recovery Act. 40 C.F.R. pts. 144, 148. See Section 12.2: Hazardous Wastes.

Wellhead Protection Program

The SDWA also encourages states to develop and submit wellhead protection programs aimed at protecting the surface and subsurface areas surrounding a water well or wellfield serving a public water system. 42 U.S.C. sec. 300h-7. Federal grants are available to states that choose to develop a wellhead protection program. A similar program exists to encourage states to adopt critical aquifer protection areas. 40 C.F.R. pt. 149.

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9.6 Water Quantity and Usage


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State law typically governs most water quantity and usage issues. The two major doctrines for surface water acquisition are the doctrine of riparian use, which is dominant in the East, and the doctrine of prior appropriation, which is dominant in the West. Several states, most notably California, use a dual system employing parts of both the riparian and prior appropriation doctrines. Originally, these systems developed through the common law, but now most states have enacted regulatory programs and permit systems that govern water use and acquisition.

Under the riparian use doctrine, owners of property contiguous to a water course can make reasonable use of the water, including diverting it for consumptive uses within the watershed, as long as the use does not unreasonably interfere with other riparian owners' use. In dry years, water will be prorationed or shared among users.

Under the prior appropriation doctrine, the first person to divert water and put it to a beneficial use obtains the right to use that water in perpetuity. In dry years, there is no prorationing of water among users; the person with the oldest right gets the entire amount of water she has historically put to beneficial use. Later appropriators receive water only to the extent it is available in any given year.

Public Rights to Water

Both riparian and prior appropriation states may be limited by "public" rights to the water. First, federal statutes can preempt state water laws for some purposes, such as the regulation and development of hydroelectric power. First Iowa Hydro-Electric Co-op. v.Federal Power Commission, 328 U.S. 152, 66 S. Ct. 906, 90 L. Ed. 1143(1946). Several federal laws also preserve instream flows, most notably the Federal Wild and Scenic Rivers Act. 16 U.S.C. secs. 1271-1287. Second, private water rights may be subject to a navigation servitude that gives the public an inherent right to passage on navigable waters. Third, the public trust doctrine may place a limit on the ability of states to privatize certain waters. In some states, the public trust doctrine preserves certain public rights, such as to navigation or to fish in the water. Illinois Central Railroad Co. v. Illinois, 146 US 387, 13 S. Ct. 110, 36 L. Ed. 1018 (1892). There may also be implied federal reserved water rights attached to national parks, wilderness areas, and tribal reservations. Winters v. United States, 207 U.S. 564, 28 S. Ct. 207 (1908) (tribal rights); Arizona v. California, 376 U.S. 340, 84 S. Ct. 755 (1963). Finally, state laws can statutorily protect instream flows either by allowing state agencies to apply for instream water rights or by statutorily identifying specific waters to be protected.

Groundwater Allocation

Rules governing groundwater may be different than those governing surface water. There are five major doctrines for groundwater appropriation: (1) ownership of all groundwater that can be captured, regardless of the impact on neighboring wells; (2) the "reasonable use" rule, which allows landowners a "reasonable amount" of groundwater for applying to beneficial use on overlying land; (3) a rule that prohibits any use that causes unreasonable harm by lowering water tables, reducing artesian pressure, or substantially affecting a watercourse; (4) the correlative rights rule, which is applied primarily in California and which roughly apportions the amount of groundwater according to the percentage of land owned relative to the total land overlying the aquifer; and (5) the prior appropriations rule, which gives priority according to when a well was drilled.

Bureau of Reclamation

The federal Reclamation Act of 1902, ch. 1093, 32 Stat. 388 (codified as amended at 43 U.S.C. secs. 371-379, 383-600), created the U.S. Department of the Interior's Bureau of Reclamation to construct dams, canals, and other water works to develop the arid West's water resources. These projects are managed by irrigation districts under contract to the Bureau of Reclamation, but state law still governs the allocation of water between such projects and other water users.

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9.7 Protection of Fresh Water Ecosystems


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See also Section 15: Private Land Use Planning and Management; Section 17.4: Protection of Habitats and Ecosystems; and, Section 25: Transboundary and International Issues.

Free-Flowing Rivers

The federal Wild and Scenic Rivers Act, 16 U.S.C. secs. 1271-1287, creates a national system for protecting free-flowing rivers with remarkable scenic or recreational values. Rivers are designated as either "wild," "scenic," or "recreational," depending on the level of development along the river. Rivers can either be designated by Congress or by state initiative if the Secretary of the Interior approves and the state agrees to administer the river. 16 U.S.C. sec. 1273. No activities, including logging, water diversions, or development projects that could conflict with the purposes of the wild and scenic designation are allowed on designated rivers. Mining activities based on rights that pre-date river designation are allowed. Management plans regulating activities on adjacent lands must be developed for all rivers designated after 1985.


The primary federal law protecting wetlands is the Clean Water Act (CWA). Wetlands are a subset of waters of the United States, which are identified based on their soil, hydrology, and vegetation. 40 C.F.R. sec. 230.41. Discharges dredged or fill material from point sources into wetlands require a permit from the Army Corps of Engineers. See CWA, 33 U.S.C. sec. 1344; 33 C.F.R. pt. 323. EPA retains enforcement authority and authority to set the substantive guidelines that the Army Corps must follow in issuing these permits. 33 U.S.C. sec. 1344(b)(1); 33 C.F.R. pt. 323; 40 C.F.R. sec. 230.41. In addition, EPA issues permits for point source discharges of pollutants other than dredged or fill material.

The Army Corps is authorized to issue general, regional, state, or national permits that allow certain categories of wetland filling activities without the need to obtain individual permits. 33 U.S.C. sec. 1344(e). Projects will not receive permits if: a practicable alternative with less impact exists; the activity would violate state water quality standards, would violate any toxic effluent standard, would jeopardize an endangered species, or would harm a marine sanctuary; the activity would cause significant degradation of any waters; or, the activity has not included appropriate steps for minimizing potential adverse impacts on aquatic ecosystems. 40 C.F.R. sec. 230.10. The federal wetlands permit requirements allow several narrow exemptions, including routine farming activities, maintenance of dams and other infrastructure, construction of farm ponds or roads, or actions authorized by an approved state program. 33 U.S.C. sec. 1344(f). Several federal agricultural programs are also designed to preserve wetlands.


Estuaries, which are coastal bays or rivers and their freshwater tributaries, provide resources for diverse uses including transportation, recreation, and natural habitat. The Clean Water Act Amendments of 1987 (P.L. 100-4) established the National Estuary Program to identify nationally significant estuaries that are threatened by pollution, land development, or overuse, and to award grants that support the development of comprehensive management plans to restore and protect them. State governors nominate estuaries within their states to be admitted into the National Estuary Program. The 106th Congress enacted the Estuaries and Clean Waters Act of 2000 (P.L. 106-457), which reauthorized the program.

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9.8 Liability and Enforcement


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EPA has broad inspection and monitoring powers to administer and enforce both the CWA and the SDWA. For example, EPA can enter and inspect property, equipment and records, it can require specific self-monitoring, and it can take discharge samples. CWA, 33 U.S.C. sec. 1318; SDWA, 42 U.S.C. sec. 300j-4.

Federal Enforcement of the CWA

Three basic civil enforcement tools are available to EPA: administrative orders requiring compliance, administrative penalties, and civil actions to collect penalties or obtain an injunction. 33 U.S.C. secs. 1319, 1321. Separate enforcement provisions apply to oil discharges, 33 U.S.C. sec. 1321, and to dredging and filling activities of waters of the United States requiring a permit from the Army Corps of Engineers. 33 U.S.C. sec. 1344(s) . EPA retains almost complete discretion to negotiate and settle its civil or administrative enforcement actions. Actual fines are calculated according to specific penalty policies or guidelines, which typically emphasize the severity, frequency, and duration of the violation. Settlements also typically include a consent order creating a specific timetable for compliance and stipulated penalties for violations of the consent order.

Federal Enforcement of the SDWA

Primary enforcement of the SDWA is delegated to the states, 42 U.S.C. sec. 300h-1, but EPA can issue an order to a state requesting enforcement. EPA has independent enforcement avenues available as well. It can issue an administrative order requiring compliance or assessing administrative penalties, or it can commence a civil action to collect penalties or obtain an injunction. EPA also has broad emergency authority whenever contamination of a water supply poses an "imminent and substantial endangerment" to public health. 42 U.S.C. sec. 300i.

Liability Under the CWA

The CWA holds owners or operators of any facility or vessel causing a discharge of oil or hazardous substances liable for all response costs of the government, up to certain specified limits. Third parties who cause the discharge may also be held liable. The federal government is granted broad emergency authority to respond to any discharges that may pose a "substantial threat" to public health or welfare. 33 U.S.C. sec. 1321.

Oil Pollution Act of 1990

In response to the Exxon Valdez oil spill, Congress passed the Oil Pollution Act of 1990, a comprehensive liability law similar to the Comprehensive Environmental Response, Compensation and Liability Act CERCLA, but applicable to discharges of oil. 33 U.S.C. sec. 2701-2719. Any owner or operator (or other responsible party) of a vessel or facility that discharges or threatens to discharge oil into navigable waters, adjoining shorelines, or the U.S. exclusive economic zone is liable up to a certain limit for removal costs consistent with the National Contingency Plan (NCP) and for certain damages. 33 U.S.C. sec. 2702(a). Any third party found to be the sole cause of a discharge can also be held liable as a responsible party. 33 U.S.C. sec. 2702(d). See Section 13: Responding to Environmental Contamination. Additionally, the 1990 Oil Pollution Act established an Oil Spill Liability Trust Fund. 26 U.S.C. sec. 9509

Financial Responsibility

All owners or operators of vessels over 300 gross tons, all offshore facilities, and all deepwater ports must establish evidence of financial responsibility at least equal to the limits of liability to which they could be subjected. 33 U.S.C. sec. 2716(a).

State Enforcement

The states are considered the primary enforcers of water quality standards under the CWA, although the federal government retains extensive authority to inspect, enter, or monitor facilities, and to bring enforcement actions. 33 U.S.C. sec. 1319. Under the SDWA, in states that have not retained primary enforcement responsibility (primacy), enforcement is the responsibility of the EPA.

Citizen Suits

Both the CWA and SDWA allow citizen suits. Under the CWA, a citizen can bring a civil action against any person who violates any effluent standard or any limitation under the Act. Citizens can also sue to force EPA to carry out any non-discretionary duty under the CWA. 33 U.S.C. sec. 1365. The SDWA allows citizens to sue any person, including federal and state government agencies, who are not in compliance. 42 U.S.C. sec. 300j-8

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