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Water: Water Quality Standards

Water Quality Standards History

Why are WQS Important?] [WQS Review and Revision] [Role of the Public] [Designated Uses] [Water Quality Criteria] [Antidegradation] [General Policies] [Indian Tribe Participation] [WQS Program History]

Statutory History

The first comprehensive legislation for water pollution control was the Water Pollution Control Act of 1948 (Pub. L. 845, 80th Congress). This law adopted principles of state and federal cooperative program development, limited federal enforcement authority, and limited federal financial assistance. These principles were continued in the Federal Water Pollution Control Act (Pub. L. 660, 84th Congress) in 1956 and in the Water Quality Act of 1965. Under the 1965 Act, States were directed to develop water quality standards establishing water quality goals for interstate waters. By the early 1970's, all the States had adopted such water quality standards. Since then, States have revised their standards to reflect new scientific information, the impact on water quality of economic development and the results of water quality controls.

Due to enforcement complexities and other problems, an approach based solely on water quality standards was deemed insufficiently effective. In the Federal Water Pollution Control Act Amendments of 1972 (Pub. L. 92500, Clean Water Act or CWA), Congress established the National Pollutant Discharge Elimination System (NPDES) whereby each point source discharger to waters of the U.S. is required to obtain a discharge permit. The 1972 Amendments require EPA to establish technology based effluent limitations that are to be incorporated into NPDES permits. In addition, the amendments extended the water quality standards program to intrastate waters and required NPDES permits to be consistent with applicable state water quality standards. Thus, the CWA established complementary technology-based and water quality-based approaches to water pollution control.

Water quality standards serve as the foundation for the water-quality based approach to pollution control and are a fundamental component of watershed management. Water quality standards are State or Tribal law or regulation that: define the water quality goals of a water body, or segment thereof, by designating the use or uses to be made of the water; criteria necessary to protect the uses; and protect water quality through antidegradation provisions. States and Tribes adopt water quality standards to protect public health or welfare, enhance the quality of water, and serve the purposes of the Act. "Serve the purposes of the Act" (as defined in Sections 101(a), 101(a)(2), and 303(c) of the Act) means that water quality standards should: 1) include provisions for restoring and maintaining chemical, physical, and biological integrity of State waters, 2) provide, wherever attainable, water quality for the protection and propagation of fish, shellfish, and wildlife and recreation in and on the water ("fishable/swimmable"), and 3) consider the use and value of State waters for public water supplies, propagation of fish and wildlife, recreation, agricultural and industrial purposes, and navigation. See 40 CFR 131.2.

Section 303(c) of the CWA establishes the basis for the current water quality standards program. Section 303(c):

  1. Defines water quality standards;
  2. Identifies acceptable beneficial uses: propagation of fish, shellfish and wildlife, public, agricultural, industrial water supplies and navigation;
  3. Requires that State and Tribal standards protect public health or welfare, enhance the quality of water and serve the purposes of the Act;
  4. Requires that States and Tribes review their standards at least every three years;
  5. Establishes the process for EPA review of State and Tribal standards, including where necessary the promulgation of a superseding Federal rule in cases where a State's or Tribe's standards are not consistent with applicable requirements of the CWA or in situations where the Administrator determines that Federal standards are necessary to meet the requirements of the Act.

The decade of the 1970's saw State and EPA attention focus on creating the infrastructure necessary to support the NPDES permit program and development of technology-based effluent limitations. While the water quality standards program continued, it was a low priority in the overall CWA program. In the late 1970's and early 1980's, it became obvious that greater attention to the water quality-based approach to pollution control was needed to effectively protect and enhance the nation's waters.

The first statutory evidence of this was the enactment of a CWA requirement that after December 29, 1984, no construction grant could be awarded for projects that discharged into stream segments which had not, at least once since December 1981, had their water quality standards reviewed and revised or new standards adopted as appropriate under Section 303(c). The efforts by the States to comply with this onetime requirement essentially made the States' water quality standards current as of that date for segments with publicly-owned treatment works (POTWs) discharging into them.

Additional impetus to the water quality standards program occurred on February 4, 1987, when Congress enacted the Water Quality Act of 1987 (Pub. L. 1004). Congressional impatience with the lack of progress in State adoption of standards for toxics (which had been a national program priority since the early 1980's) resulted in the 1987 adoption of new water quality standard provisions in the Water Quality Act amendments. These amendments reflected Congress' conclusion that toxic pollutants in water are one of the most pressing water pollution problems. One concern Congress had was that States were relying, for the most part, on narrative criteria to control toxics (e.g. "no toxics in toxic amounts"), which made development of effluent limitations in permits difficult. To remedy this, Congress adopted section 303(c)(2)(B), which essentially required development of numeric criteria for those water body segments where toxic pollutants were likely to adversely affect designated uses.

The 1987 Amendments gave new teeth to the control of toxic pollutants. As Senator Mitchell put it, Section 303(c)(2)(B) requires "States to identify waters that do not meet water quality standards due to the discharge of toxic substances, to adopt numerical criteria for the pollutants in such waters, and to establish effluent limitations for individual discharges to such water bodies."." (From Senator Mitchell, 133 Cong. Rec. S733).

To assist States in complying with Section 303(c)(2)(B), EPA issued program guidance in December 1988 and instituted an expanded program of training and technical assistance.

Section 518 was another major addition in the 1987 Amendments to the Act. This section extended participation in the water quality standards and 401 certification programs to certain Indian Tribes. The Act directed EPA to establish procedures by which a Tribe could "qualify for treatment as a State," at its option, for purposes of administering the standards and 401 certification programs. The Act also required EPA to create a mechanism to resolve disputes that might develop when unreasonable consequences arise from a Tribe and a State or another Tribe adopting differing water quality standards on common bodies of water.

Furthermore, with the 1987 Amendments, the Act explicitly recognized EPA's antidegradation policy for the first time. The intent of the antidegradation policy in EPA's regulation was and is to protect existing uses and the level of water quality necessary to protect existing uses and to provide a means for assessing activities that may lower water quality in high quality waters. Section 3O3(d)(4) of the Act requires that water quality standards in those waters that meet or exceed levels necessary to support designated uses "may be revised only if such revision is subject to and consistent with the antidegradation policy established under this section."

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Regulatory Requirements and Guidance

In the late 1960's and early 1970's the water quality standards program was initiated and administered based on minimal guidance and Federal policies--many of which are still reflected in the water quality standards program today.

EPA first promulgated a water quality standards regulation in 1975 (4O CFR 13O.17, 4O FR 55334, November 28, 1975) as part of EPA's water quality management regulations mandated under Section 3O3(e) of the Act. As discussed earlier, the standards program had a relatively low priority during this time. This was reflected in the minimal requirements of the first Water Quality Standards Regulation. Few requirements on designating water uses and procedures were included. The Regulation merely required "appropriate" water quality criteria necessary to support designated uses. Toxic pollutants or any other specific criteria were not mentioned. The antidegradation policy was incorporated as a regulatory requirement.

State response to the initial regulation was varied and in some cases inadequate. Some States developed detailed water quality standards regulations while others adopted only general provisions which proved to be of limited use in the management of increasingly complex water quality problems. The few water quality criteria that were adopted addressed a limited number of pollutants and primarily described fundamental water quality conditions (e.g., pH, temperature, dissolved oxygen and suspended solids) or dealt with conventional pollutants.

In the late 1970s, a greater appreciation evolved on the need to expand and accelerate the control of pollutants in surface waters using water quality-based controls. It became clear that primary reliance on industry effluent guidelines or effluent standards under Section 3O7 of the Act would not comprehensively address pollutants, particularly toxic pollutants, and that existing State water quality standards needed to be better developed. EPA moved to strengthen the water quality program to complement the technology based controls.

To facilitate this effort, EPA decided to amend the Water Quality Standards Regulation to explicitly address toxic criteria requirements in State standards and other legal and programmatic issues. This effort culminated in the promulgation of a revised water quality standards regulation on November 8, 1983 (54 FR 51400), which is still in effect. This regulation is much more comprehensive than its predecessor and it includes many more specific regulatory and procedural requirements. Nonetheless, it is still a succinct and flexible regulation for a program with a scope as broad as the national water quality criteria and standards program.

The regulation specifies the roles of the States, Tribes and EPA and the administrative requirements for States and Tribes in adopting and submitting their standards to EPA for review. It also delineates the EPA requirements for review of State and Tribal standards and promulgation of federal standards.

The regulation provided States and subsequently Tribes with the option of refining their use designation process by allowing them to establish subcategories of uses, such as cold water and warm water aquatic life designations. The regulation expanded and clarified the factors that could be applied by a State in removing a designated use that is not an existing use. The regulation recognized that naturally occurring pollutant concentrations, naturally low or intermittent flow conditions, human caused conditions or sources of pollution that cannot be remedied, hydrologic modifications (such as dams or channelized streams), natural physical conditions, and widespread economic and social impact could be used to demonstrate that attaining a use designation is not feasible (see 40 CFR 131.10(g)). Part 131.10(h) identified circumstances in which States are prohibited from removing designated uses.

Much more specificity was provided in the 1983 regulation regarding the requirements for States on the form of water quality criteria adopted by the States. Under 40 CFR 131.11(b) of the regulation, States and Tribes may use the criteria developed by EPA under Section 304(a) of the Act, 304(a) guidance modified to reflect site-specific conditions, or criteria developed through other scientifically defensible methods. Section 304(a) criteria are the water quality criteria that EPA develops and provides in the form of guidance to States and Tribes pursuant to CWA section 304(a). In practice, States and Tribes have applied all of these provisions in setting water quality standards.

The 1983 regulation also clarified that States and subsequently Tribes may adopt discretionary policies affecting the implementation of standards, such as mixing zones, low flows, and variances. Such policies are subject to EPA review under 303(c). Section 131.11 of the regulation requires States and subsequently Tribes with water quality standards programs to review available information and "…to identify specific water bodies where toxic pollutants may be adversely affecting water quality …and… adopt criteria for such toxic pollutants applicable to the water body sufficient to protect the designated use."

Under the statutory scheme, during the 3-year review period following EPA's 1980 publication of section 304(a) water quality criteria to the protect human health and aquatic life, States were expected to review those criteria and adopt standards for many priority toxic pollutants. A few States adopted large numbers of numeric toxics criteria, primarily for the protection of aquatic life. Other States adopted few or no water quality criteria for priority toxic pollutants. Some relied on a narrative "free from toxicity" criterion, and "action levels" for toxic pollutants or occasionally calculated site-specific criteria. Few States addressed the protection of human health by adopting numeric human health criteria.

In support of the 1983 Regulation, EPA simultaneously issued program guidance entitled Water Quality Standards Handbook (December, 1983). The Handbook provided guidance on the interpretation and implementation of the Water Quality Standards Regulation. This document also contained information on scientific and technical analyses that are used in making decisions that would impact water quality standards. EPA also developed the Technical Support Document for Water Quality Based Toxics Control (EPA 44/485032, September,1985)(TSD) which provided additional guidance for implementing State water quality standards. In 1991, EPA revised and expanded the TSD. (EPA 505/2-90-001, March 1991). In 1994, EPA issued the Water Quality Standards Handbook: Second Edition (EPA-823-B-94-006, August 1994).

To accelerate compliance with CWA section 303(c)(2)(B) (created by the 1987 Water Quality Act), EPA started action in 1990 to promulgate numeric water quality criteria for those States that had not adopted sufficient water quality standards for toxic pollutants. The intent of the rule making, known as the National Toxics Rule, was to strengthen State water quality management programs by increasing the level of protection afforded to aquatic life and human health through the adoption of all available criteria for toxic pollutants present or likely to be present in State waters. This action culminated on December 22, 1992, with EPA promulgating Federal water quality criteria for priority toxic pollutants for 14 States and Territories (see 57 FR 60848).

Subsequent to the promulgation of criteria under the National Toxics Rule, EPA altered its national policy on the expression of aquatic life criteria for metals. On May 4, 1995 at 60 FR 22228, EPA issued a stay of several metals criteria (expressed as total recoverable metal) previously promulgated under the National Toxics Rule for the protection of aquatic life. EPA simultaneously issued an interim final rule that changed these metal criteria promulgated under the National Toxics Rule from the total recoverable form to the dissolved form.

The Water Quality Standards Regulation was amended in 1991 to implement Section 518 of the Act to expand the standards program to include Indian Tribes (56 FR 64893, December 12, 1991). EPA added 40 CFR 131.7 to describe the requirements of the issue dispute resolution mechanism (to resolve unreasonable consequences that may arise between a Tribe and a State or another Tribe when differing water quality standards have been adopted for a common body of water) and 40 CFR 131.8 to establish the procedures by which a Tribe applies for authorization to assume the responsibilities of the water quality standards and section 401 certification programs.

Water quality standards are essential to a wide range of surface water activities, including: (1) setting and revising water quality goals for watersheds and/or individual water bodies, (2) monitoring water quality to provide information upon which water quality based decisions will be made, (3) calculating total maximum daily loads (TMDLs), waste load allocations (WLAs) for point sources of pollution, and load allocations (LAs) for non point sources of pollution, (4) issuing water quality certifications for activities that may affect water quality and that require a federal license or permit, (5) developing water quality management plans which prescribe the regulatory, construction, and management activities necessary to meet the water body goals, (6) calculating NPDES water quality-based effluent limitations for point sources, in the absence of TMDLs, WLAs, LAs, and/or water quality management plans; (7) preparing various reports and lists that document the condition of the State's or Tribe's water quality, and (8) developing, revising, and implementing an effective section 319 management plan which outlines the State's or Tribe's control strategy for non point sources of pollution.

Also, as described in EPA's 40 CFR 131.21, EPA requires that water quality standards adopted by states and authorized tribes on or after May 30, 2000 must be approved by EPA before they can be used as the basis for actions, such as establishing water quality-based effluent limitations or toal maximum daily loads (TMDLs), under the Clean Water Act. (See 65 FR 24641, April 27, 2000, for more information regarding this requirement).

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