Wetland Water Quality Standards


Water quality standards (WQS) are the foundation of the water quality-based pollution control program mandated by the Clean Water Act (CWA). They define the goals for a water body by designating its highest attainable uses, setting criteria that reflect the current and evolving body of scientific information to protect those uses, and establishing provisions to protect water bodies from further degradation.

WQS developed specifically for wetlands help ensure that the provisions of the Clean Water Act, are consistently applied to wetlands; they also provide a more relevant scientific basis for applying these provisions. WQS for wetlands are developed by states, territories, and authorized tribes in accordance with EPA’s regulations at 40 CFR Part 131.

Standards can be derived and supported using measurements of wetland function or condition. This typically involves intensive data collection dependent on a successful wetland monitoring and assessment program. Due to the unique characteristics of wetlands relative to flowing surface waters, water quality standards for wetlands may differ from other surface water standards. For example, they may rely less on water chemistry parameters and more on diversity of vegetation or macroinvertebrate communities. Wetland standards may also differ from surface water standards by relying on additional parts of state laws and regulations that do not apply to instream water quality.

Generally, a suite of measures will be required for wetland WQS to protect the full range of wetland functions and/or ecological condition. As with water quality criteria for other surface waters, criteria for wetlands can be narrative or numeric. Given their complexity, narrative (rather than numeric) criteria may be most adaptive and the preferred approach for states, territories, and authorized tribes when first developing WQS for wetlands. EPA provides narrative templates for wetland WQS as a tool to assist in their development.

Goals and Benefits

Water quality standards (WQS) for wetlands can provide a strong foundation for protecting and enhancing state or tribal wetland resources and are one of the four core elements of effective state and tribal wetlands programs.  Wetland WQS can provide the basis for actions leading to an "overall increase" in wetland function and condition, one of EPA's national wetland goals. They also provide the scientific basis for a variety of actions to protect and restore wetlands, such as:

In addition, wetland WQS provide the basis for decisions in other programs that affect wetlands such as the Total Maximum Daily Loads and nonpoint source pollution control programs. States, territories, and authorized tribes can successfully adopt and apply WQS for wetlands by pursuing the following objectives:

  1. Ensure that wetlands are treated as waters within state and tribal water quality programs.
  2. Develop wetland-specific water quality standards; and
  3. Incorporate wetland-specific water quality standards into agency decision-making.

How Do I Develop and Use Wetland Water Quality Standards?

Program Building Activities Menu

Wetland water quality standards are one of the core elements of effective state and tribal wetlands programs. The activities menu below provides actions and measures of progress for states, territories, and authorized tribes (states) interested in developing, adopting, and incorporating water quality standards into their wetlands programs to improve wetland protection. The menu is intended to provide a comprehensive set of activities that states can select and implement based on their own program goals and available resources.

Narrative Templates

EPA and state water quality and wetland associations partnered to develop an online tool to assist states, territories, and authorized tribes (states) with developing protective and comprehensive narrative water quality standards for wetlands.  The templates provide states with wetland-related terms to select from for developing water quality standards that best suit the needs of, and conditions in, a given wetland, wetland type or state.


References have been compiled in the resources document below in an effort to offer additional information to states, territories, and authorized tribes interested in developing or improving wetland water quality standards. This list of resources is not intended to promote any one technical approach or pathway over another but rather to serve as a source of both current and historic information that may be considered by states, territories, and authorized tribes along with other relevant information. While some of these materials are dated, they can still offer helpful background or principles for consideration.

You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more.

You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more.