Water Quality Standards

Water quality standards and classifications vary from state to state. States classify waterbodies based on their uses, such as drinking water, contact recreation, and aquatic life support. Criteria are then implemented to ensure a waterbody will safely support the specified uses.

States have criteria for a wide variety of issues including bacteria and nutrients.

Criteria can be either numeric or narrative. To guide state standards, EPA has created water quality criteria for hundreds of pollutants. Additionally, standards exist as part of an antidegradation policy to prevent the deterioration of water quality.

Antidegradation requires that existing waterbody uses and the level of water quality necessary to protect those existing uses be maintained and protected.

View from a bridge

Development of appropriate water quality standards is the core component of the Clean Water Act because water quality standards influence so many other CWA programs. These include water quality monitoring, total maximum daily loads (TMDLs), National Pollutant Discharge Elimination System (NPDES) permits, nonpoint source programs, oceans and wetland programs, and source water protection.

Below is a summary of just a few of the ways in which NEIWPCC is involved with the information sharing, development, and implementation of water quality standards.

Water Quality Monitoring

An integral part of the Clean Water Act equation, monitoring can be used to assess the types and sources of pollution loading into a watershed, to determine the progress of current water quality programs, and to document the health of watersheds. Section 305(b) of the Clean Water Act requires all states to provide a report on the status of their water bodies on a biennial basis. The ten elements in a statewide monitoring program that are required in the Comprehensive Monitoring Strategy are as follows:

  • A monitoring program strategy
  • Monitoring objectives
  • A monitoring design
  • Core and supplemental water quality indicators
  • Quality assurance
  • Data management
  • Data analysis and assessment
  • A reporting scheme
  • A programmatic evaluation
  • General support and infrastructure planning

The U.S. EPA hosts a workgroup that meets annually to discuss relevant policy, funding and scientific issues related to water quality monitoring.

Water Quality Standards Workgroup

NEIWPCC has a Water Quality Standards Workgroup, which comprises our state and federal partners. This group meets twice a year or on an as-needed basis. The goal of the workgroup is not to seek uniformity in the states’ standards and classifications but rather to identify interstate water quality issues.

The group provides a forum in which to develop solutions and identify and avoid potential future issues through improved communication. Two tools that we have developed through this workgroup process are our interstate matrices, which summarize our member states’ water quality standards and waterbody designated uses and classifications.

The NEIWPCC staff closely follows any developments and changes to our states’ water quality standards and related litigation. As new water chemistry and toxicity studies are released, the states and EPA each compile and analyze relevant evidence for a particular toxin or parameter to determine if updates to criteria are necessary. All state water quality standards must be reviewed every three years and formally submitted and maintained in EPA’s Water Quality Docket.

In addition to developing specific criteria guidance and standards, states must also respond to new and revised regulations and rules proposed by EPA. Some recent rulemaking highlights include EPA proposals to clarify water quality standards regulation, to help states determine which streams and wetlands are protected by the CWA, and to update bacteria criteria for protection of human health in recreational waters.

NEIWPCC works with the Water Quality Standards Workgroup to help states provide a unified regional response to proposed rules through comment letters, and then facilitates discussions on how states can best approach implementation once the rules are finalized.

For more information on water quality standards and our workgroup, contact Emma Gildesgame, the coordinator of our Water Quality Standards Workgroup.