Join us.

We’re working to create a just society and preserve a healthy environment for future generations. Donate today to help.


The CWA’s Antidegradation Policy: Time to Rejuvenate a Program to Protect High Quality Water

Climate Justice

This post was written by CPR Member Scholars Robert Glicksman and Sandra Zellmer.

Visual images of burning rivers, oil-soaked seagulls, and other grossly contaminated resources spurred the enactment of the nation’s foundational environmental laws in the 1970s, including the Clean Water Act (CWA). Similarly, evocative prose like Rachel Carson’s description of the “strange blight” poisoning America’s wildlife due to widespread use of pesticides played a critical role in alerting policymakers and the public to the need for robust legal protections for public health and the environment. 

Environmental law, however, has always been about more than just repairing the damage wrought by past disasters or resource mismanagement. Senator Edmund Muskie, the principal sponsor of the CWA, was moved to action not only by the despoliation he witnessed but also by “the beauties of nature . . . in almost pristine form” he marveled at while growing up. 

Antidegradation Goals

The reasons to mandate the improvement of inferior quality natural resources are relatively obvious, and include ensuring that exposure to, or use of, those resources does not adversely affect human health, destroy critical wildlife or fish populations, or otherwise disrupt ecosystem functions. By contrast, no single goal explains legal mandates to prevent degradation of superior quality resources.  Instead, antidegradation programs in the CWA and in other environmental laws rest on a variety of rationales, including the desire to protect special or unique resources, to provide a margin of safety to offset the risk that regulations will not provide enough protection due to imperfect knowledge or flawed regulatory implementation, to prevent the movement of industry to areas with superior environmental quality but more lenient requirements, to prevent interstate pollution, and to preserve opportunities for future generations and future growth.

The CWA’s antidegradation program is consistent with those goals.  Among the CWA’s principal goals are “to restore and maintain the chemical, physical, and biological integrity” of the nation’s surface waters (emphasis added).  True, the Act’s adoption was spurred by the realization that unchecked pollution had caused extensive degradation of those waters, making them utterly unsuitable for drinking, fishing, and recreation. At the time Congress passed the statute, however, some lakes, rivers, and streams had water quality that was better than what was needed to support basic uses and needs.  An important question was whether the statute should limit pollution discharges that could impair these high quality waters.  The U.S. Environmental Protection Agency’s (EPA) antidegradation policy provided an affirmative answer.  The EPA was building on then-existing guidelines issued by the Department of Interior, which administered a predecessor statute, the 1965 Water Quality Act, and a wide variety of statutes on the management of Wildlife Refuges, National Parks, and the protection of wildlife species.  Interior’s initial guidelines provided that “in no case will standards providing for less than existing water quality be acceptable,” and required that standards provide for “the maintenance and protection of quality and use or uses of water now of a higher quality or of a quality suitable for present and potential uses.” 

EPA refined its policy in 1975, creating the requirements that, with few changes, remain in place today.  Although Congress did not expressly include an antidegradation policy in the 1972 CWA, in 1987, it cryptically endorsed EPA’s approach to antidegradation.  The statute was amended to provide that for waters whose quality exceeds levels necessary to protect designated uses, any effluent limitation based on a total maximum daily load (TMDL)—the maximum pollutant loading that a water body can assimilate without violating water quality standards—may be revised only if the revision “is subject to and consistent with the antidegradation policy established under this section,” thereby incorporating by reference EPA’s administrative policy.

The Requirements of EPA’s Antidegradation Policy

Today, an antidegradation policy is a required component of the water quality standards that states must adopt and enforce (see PUD No. 1 of Jefferson County v. Washington Dep’t of Ecology).  EPA regulations direct the states to include three antidegradation elements in their water quality standards (see C.F.R. 131.12, and the EPA Handbook chapter on this section).  First, existing instream uses, and the level of water quality necessary to protect those uses, must be maintained and protected—state standards must be “sufficient to maintain existing beneficial uses of navigable waters, preventing their further degradation.”  Second, the state must maintain water quality that exceeds levels necessary to support recreation and the propagation of fish and wildlife, unless allowing lower water quality is necessary to accommodate important economic or social development.  Even then, water quality standards must fully protect existing uses.  In addition, the state must assure achievement of the highest statutory and regulatory requirements for all point sources, as well as reasonable best management practices for nonpoint sources.  Third, the state must maintain quality in high quality waters that constitute an “outstanding National resource,” including waters of national and state parks, wildlife refuges, and waters of “exceptional recreational or ecological significance.” 

In short, the policy requires different levels of protection for three types, or tiers, of waters.  Under Tier 1, existing uses must be maintained in all waters.  Under Tier 2—high-quality waters that exceed fishable/swimmable quality—degradation will be allowed only if it is necessary to accommodate important social or economic development in the region. Degradation of water quality is completely prohibited for Tier 3, Outstanding National Resource Waters (“ONRWs”), although “temporary and short-term changes” in quality to accommodate important economic uses are allowed.  Thus, the policy is designed to protect both existing uses and existing water quality, but in different circumstances.  The Tier 1 provisions are directed at protecting existing uses, while Tier 2 aims to protect water quality. Tier 3 also protects high water quality.

The Flaws in Implementation of the Antidegradation Policy

Despite the long history of attempts to protect superior water quality, the CWA’s antidegradation goal has taken a back seat to statutory goals for minimizing pollution and preventing further impairment of polluted waters.  The problem lies not only in the cryptic language of the statute and EPA’s regulations, but also in inadequate federal and state implementation practices.

The EPA’s antidegradation policy is by no means a precise set of instructions to the states. EPA interprets its role in the enforcement of antidegradation policies as a passive one.  It may disapprove and promulgate all or part of an implementation process for antidegradation if, in the judgment of the Administrator, the state’s process (or provisions thereof) circumvents the intent and purpose of the antidegradation policy.  EPA rarely does so, however.  EPA’s proclivity for leaving the policy vague, and for affording broad discretion to the states, has precluded the development of a consistent national antidegradation policy. As a result, critics describe the policy as “at best, obscure,” and lacking in substantive content.

In particular, the states’ designation criteria and processes vary tremendously. EPA’s antidegradation policy does not provide adequate guidance on how to distinguish between Tier 1 and Tier 2 waters.  Likewise, EPA’s definition of Tier 3 (ONRWs) is unclear.  Moreover, some states’ regulations provide no information whatsoever on how a water body might be nominated or how a designation decision might be made. “Designation policies in many states are so vague as to be hard for a concerned citizen or watershed group to use . . . or even to understand how they could use them,” argues a paper by the River Network.  Exacerbating the problem is the tendency of courts to defer to the agencies’ designation decisions, unless there is absolutely no evidence to support them. This deferential posture precludes holding state agencies or EPA accountable for weak implementation of the CWA’s antidegradation mechanisms.

With respect to the most protective category—Tier 3 ONRWs—some states have no regulations regarding processes or criteria for making designation decisions. Not surprisingly, then, some states have no ONRWs within their boundaries. EPA regulations include as examples of ONRWs “waters of National and State parks and wildlife refuges and waters of exceptional recreational or ecological significance.”  These waters are not covered, however, unless a state takes affirmative steps to designate them, and states sometimes refuse to do so for fear that ONRWs, which are afforded the highest level of protection, would stymie economic development. 

Even when water bodies do get designated, the states’ permitting decisions—and the EPA’s oversight of those decisions—have not ensured effective protection against degradation. EPA’s lack of vigilance in overseeing state compliance with the antidegradation policy was reflected in its approval of an egregiously deficient implementation plan in Oregon.  The plan contained only one sentence providing that the state’s entire set of water quality standards was “intended to implement the Antidegradation Policy.”  When environmental groups challenged EPA’s approval, the court held that EPA erred in accepting something that failed to identify “even a semblance of an implementation plan,” in clear violation of its own regulation.  Subsequently, when EPA approved Oregon’s revised plan, its decision was remanded once again because the plan failed to specify a method to identify and protect existing uses.  Unfortunately, Oregon’s experience is by no means an isolated one.

Once a properly adopted state antidegradation program is in place, states have considerable discretion to accommodate discharges into Tier 1 and 2 waters to promote economic and social goals, provided they comply with regulatory procedures and supply some evidentiary support for their substantive determinations.  Just as beauty is in the eye of the beholder, states’ views on just how “important” economic goals must be to justify degradation varies widely.  For example, an Alabama court reasoned that the state permitting agency needed the discretion to decide whether the needs of the state’s people would be better served by placing upper limits on the costs of industrial plants than by “requiring massive and inefficient expenditures in order to achieve marginal improvements in water quality” in Tier 2 waters.  That result is symptomatic of the skepticism (if not outright antagonism) that often accompanies efforts to protect high quality waters.

One final weakness is worth noting and correcting. The exclusion of certain pollution sources has left dangerous gaps in the antidegradation program.  Many states’ antidegradation policies “are riddled with exemptions,” as a River Network paper argued.  One common exemption is for existing sources, which are typically grandfathered so long as they do not expand their discharges.  Nonpoint source exemptions are equally widespread.  Although a few states—like New Mexico, Washington, and Florida—apply antidegradation provisions to all sources of pollution in ONRWs, including nonpoint sources, most states appear to have no restrictions on nonpoint sources at all.

Reforms for the Future

We recommend four reforms to correct these problems and to strengthen the CWA’s antidegradation policy.  First, EPA should adopt a regulation requiring all states to designate high quality waters within their borders for the highest level of protection against degradation of water quality, including waters within parks and wildlife refuges. States should also be required to take concrete steps to restore the quality of degraded high quality or exceptional waters so that they can support a full suite of beneficial uses and ecosystem services.  Second, the CWA’s antidegradation program should preclude water quality impairment that either results in loss or threatened loss of an existing or potentially viable use—especially fishing, swimming, and higher uses—or adversely affects the ecological resilience of the affected water body.  Third, antidegradation requirements should be extended to cover sources that are exempt in many states, especially nonpoint sources that create polluted runoff, whether they be existing or new.  Fourth, the CWA’s antidegradation program should include mandatory state planning and assessment responsibilities, enforceable both by EPA and in citizen suits against EPA for failure to hold the states to these obligations. 

These reforms would help the CWA function as more than a rudimentary pollution control regime. They would also fulfill the objectives of the antidegradation program, especially providing a margin of safety, protecting high-value natural resources, preventing the development of pollution havens, and balancing environmental goals and economic growth opportunities.  Finally, these reforms are needed to move the nation beyond the “least common denominator” of minimally fishable/swimmable waters and toward the CWA’s overarching goal of maintaining as well as restoring the chemical, physical, and biological integrity of aquatic environments.

Climate Justice

Subscribe to CPRBlog Digests

Subscribe to CPRBlog Digests to get more posts like this one delivered to your inbox.