Photo of lake with trees around it. An example of a water body in Virginia that could be protected by the Clean water act
May 25, 2022

CWA50: Water Quality Standards and Remedying Unhealthy Waters

Water quality is a primary focus of the Clean Water Act (CWA). The CWA protects water quality by regulating pollutant discharges into surface waters so as to maintain and restore unhealthy water. But how do you know whether a lake, stream, river, estuary, or other water body is healthy? And what happens when it is not? 

Water Quality Standards: A Tool for Protecting Water Quality 

Water quality standards offer a measurement of waterbody health. Under the CWA, each state must develop water quality standards for state surface waters in order to achieve the CWA’s objective of restoring and maintaining the chemical, physical, and biological integrity of the country’s waters. A water quality standard consists of three core components: (1) a list of designated uses (such as drinking, swimming, or fishing) for all state waters; (2) the water quality criteria necessary to support those uses; and (3) antidegradation requirements. Notably, all Virginia waters are designated for recreational uses, aquatic life and wildlife, as well as fish and shellfish production. This means Virginia’s water quality standards include criteria necessary to protect recreational use, aquatic life, wildlife, and fish and shellfish production. Importantly, such water quality criteria can be numeric (e.g. expressed quantitatively using amounts) or narrative (e.g. expressed descriptively using words). Virginia’s water quality standards include narrative criteria as well as numeric criteria. 

The process of developing water quality standards is another example of cooperative federalism in the CWA. While each state, tribe, and territory has its own procedures for developing and revising standards for water quality, they must submit newly developed or revised standards to EPA for review. EPA reviews these proposed water quality standards and determines either: (a) the proposed standards satisfy CWA requirement; or (b) all or part of the proposed standards do not satisfy CWA requirements. If EPA determines that the proposed standards satisfy the CWA, then the standards become applicable meaning they are now a legal requirement. Yet, if EPA determines the standards do not satisfy the CWA, then the state must revise them or EPA may develop federal water quality standards if necessary. Moreover under the CWA, states must review and revise their approved water quality standards at least once every three years. 

In Virginia, narrative and numeric water quality criteria exist to control numerous pollutants, including but not limited to: sewage; toxic materials; oil; industrial waste; nutrients and substances causing unnatural visual impacts such as turbid conditions. Additionally, Virginia is currently undertaking a process of revising its water quality standards by developing numeric water quality criteria for turbidity or solids to supplement the current narrative criteria. Wild Virginia is engaged in this process in the effort to ensure not only robust numeric criteria for turbidity specifically, but also that Virginia enforces its water quality standards generally. 

Impaired Waters List: A Method for Identifying Unhealthy Water Quality 

The CWA also requires states to regularly assess and determine the quality of their waters, identify waters that fail to meet state water quality standards, designate these waters as “impaired,” and list them accordingly. The purpose of this list is to ensure compliance with water quality standards. Importantly, CWA regulations provide opportunities for citizen involvement in the state listing process. Citizens may submit water quality-related data and information to the relevant state, tribal, or territorial government agency overseeing water quality assessment, and these governments must consider such data and information in its assessment. This includes water quality-related data and information about water quality problems that members of the public have reported. 

Additionally, the CWA requires state, tribal, and territorial governments to document in writing their water quality assessment which must include the list of waters that do not meet “applicable water quality standards with current pollution control technologies alone.” This document is known as the Integrated Report. Notably, the Report must explain the data and information on which the state, tribal, or territorial government relied to make its listing decisions, and provide a reason for any decision not to use “relevant and readily available data” including data submitted by citizens. 

Virginia’s most recent Integrated Report, which includes its list of impaired waters throughout the Commonwealth, can be found here. Wild Virginia has advocated that DEQ acknowledge and incorporate additional information in its assessments and impairment designations and will continue to insist that the commonwealth use all available valid information.

Total Maximum Daily Loads: A Remedy for Restoring Water Quality 

Finally, for each water body listed on a state’s impaired waters list (sometimes referred to as the “303d list” after the relevant section of the CWA), the state must establish a “total maximum daily load” or TMDL for short. The TMDL limits the amount of a particular pollutant that the water can receive and still meet all applicable water quality standards. Similar to the water quality standards development process, states are responsible for developing the TMDL, proposing it to EPA, and securing EPA approval. 

Colloquially, TMDLs are often called “pollution diets” because this description helps the public understand the function and purpose of the TMDL. One of the most ambitious TMDLs is the Chesapeake Bay TMDL. After decades of local and state efforts to improve Bay water quality, the Chesapeake Bay remained impaired. This prompted New York, Pennsylvania, Delaware, Maryland, West Virginia, Virginia, and Washington, D.C. to ask EPA to develop a TMDL for the Bay. This “historical and comprehensive” TMDL is the largest EPA has ever developed, spanning 64,000 square miles of the Bay watershed including portions of six states and Washington, D.C.. This TMDL began in 2010 and has a deadline of 2025 to restore the Bay to a non-impaired state. For Virginia to meet its state Chesapeake Bay TMDL goals, each locality bears responsibility for reducing nutrient and sediment pollution

It is important to note that the public has important roles in each of the processes through which the state develops and implements its water quality standards and Wild Virginia provides information and assistance to people and allied groups to make effective comments to influence these important decisions.

***Want to learn more about water quality standards as they apply to Virginia’s waters, including how to make them work to protect our water and communities? Join Wild Virginia for a webinar on water quality standards taught by our Conservation Director, David Sligh, on Thursday June 2nd at 7pm. Register here!