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#         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:

| 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] |

Biological Indicators | 	Aquatic Biodiversity | 	Statistical Primer

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