Biocriteria Fact Sheet

Biological Criteria
National Program Guidance for Surface Waters

EPA Office of Water
Office of Science & Technology
Health and Ecological Criteria Division
May 5, 1999

Background: What Are They?

Biological criteria are narrative descriptions or numerical values that are used to describe the reference condition of aquatic biota inhabiting waters of a designated aquatic life use. They are developed by biologists and other natural resource specialists as measures to directly assess the overall condition of an aquatic community in surface waters such as streams, rivers, lakes, estuaries and wetlands. Based on appropriate reference conditions and using an array of scientific assessments and stream surveys, scientists use these criteria to determine if waters are affected by chemical pollution or other factors.

Bioassessments are an evaluation of the biological condition of a waterbody that uses biological surveys and other direct measurements of the resident biota of the waterbody. Most often, the fish population, the bottom dwelling insects and other invertebrates and plants or attached algae are evaluated.

EPA's National Biological Criteria Program began in 1988 to help fulfill the Clean Water Act objective to restore the physical, chemical, and biological integrity of the nation's waters. In 1990, EPA issued Biological Criteria: National Program Guidance for Surface Waters (EPA-440/5-90-004) as guidance for the state water pollution control agencies to assess water quality, develop water quality standards, and to determine the overall health of aquatic life in surface waters.

Who Is Using Them?

Based on a survey conducted in 1995 (Summary of State Biological Assessment Program for Rivers and Streams, US EPA 230-R-96-007) the following number of states were found to:

Use bioassessments for resource management – 41
Use bioassessments to better define aquatic life uses in waterbodies – 31
Have adopted Narrative biocriteria in State standards – 29
Have adopted Numeric biocriteria in State standards – 1*

The survey also found that many states are working on adopting both bioassessments and biocriteria to improve the way they manage water resources. EPA will assist states in their progress to use these valuable techniques. The survey will be updated by l999 to reflect state progress over the past four years.

*Numeric biological criteria based on comprehensive measures of community structure, function and/or process as recommended in EPA Technical Guidance for Streams and Small Rivers (1996) EPA-822/B-96-001.

Current Status:

EPA develops technical guidance documents for specific surface waters types (e.g. rivers, lakes, and streams). The documents outline the methods and overall approach to developing biological criteria for each water body type. These technical guidance documents are prepared by Biocriteria program workgroups which include specialist from Program Offices, other agencies, states, and academic scientists. The guidance are rigorously peer reviewed and revised before being published for state and tribal use in developing and implementing their biological criteria.

The latest biological criteria related documents to be finalized are listed below:

Biological Criteria:Technical Guidance for Streams and Small Rivers (1996) EPA-822/B-96-001
Lake and Reservoir Bioassessment and Biocriteria Technical Guidance Document (1998) EPA 841-B-98-007

The Biological Criteria program also supports the development of biological criteria by providing support to states and tribes to initiate or continue biocriteria development.

Future Steps:

EPA guidance is now being developed for the following types of water bodies to aid the states and tribes as they develop biological criteria:

Wetlands, Large rivers, Coral reefs

Estuaries and near-coastal marine waters
Statistical Methods for Biocriteria Development

Other Issues:

State water quality standards programs are most effective when they incorporate the tools which comprehensively measure chemical and physical, as well as biological integrity, therefore the National Biological Criteria program is working with states and tribes to promote the development and implementation of scientifically sound and legally defensible biological criteria in all state and tribal standards. Bioassessments and biocriteria can be used by EPA, the states and the tribes to better manage water quality throughout the Nation's waterbodies. By setting biocriteria for different waterbodies, and by assessing how well the waterbody meets the criteria the amount of water pollution and other impacts can be determined and controlled.

EPA recommends that all states and tribes use biocriteria and bioassessments in their efforts to determine water quality and to establish protective water quality standards.

Contacts:

For more information on biocriteria, contact:

Susan K. Jackson	(202) 260-1800	[email protected]
William Swietlik	(202) 260-9569	[email protected]
Donna Reed-Judkins	(202) 260-0458	[email protected]
Jennifer Mitchell	(202) 260-6101	[email protected]
Chris Faulkner	(202) 260-6228	[email protected]
Laura Gabanski	(202) 260-5868	[email protected]
Tom Gardner	(202) 260-7309	[email protected]
Wayne Davis	(410) 305-3030	[email protected]
Tom Danielson	(202) 260-5299	[email protected]

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