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Bioassessment and Biocriteria Program Status for Alabama: Streams and Wadeable Rivers

State Program Contact

Alabama Department of Environmental Management Water QualityExit

Water Quality Standards

WQS Information
The link to Alabama's WQS that are in effect for Clean Water Act purposes is provided. These are the WQS approved by EPA.
The state of Alabama provided information and links to sections of their administrative code on designated aquatic life use, biological criteria, antidegradation as well as technical support documents and information on its bioassessment and biocriteria programs. These are included for your convenience and may or may not reflect the most recently EPA approved WQS. The following links exit the site Exit

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Designated Aquatic Life Uses
335-6-10-.03 Water Use Classifications.
(1) Outstanding Alabama Water
(2) Public Water Supply
(3) Swimming and Other Whole Body Water-Contact Sports
(4) Shellfish Harvesting
(5) Fish and Wildlife
(6) Limited Warmwater Fishery
(7) Agricultural and Industrial Water Supply

Biological Criteria
__X__ Narrative statement
_____ Numeric
_____ No criteria

Chapter 335-6-10 Water Quality Criteria (PDF)(453 pp, 2 MB) Section 335-6-10-.01 Purpose. (1) Title 22, Section 22-22-1 et seq., Code of Alabama 1975, includes as its purpose "... to conserve the waters of the State and to protect, maintain and improve the quality thereof for public water supplies, for the propagation of wildlife, fish and aquatic life and for domestic, agricultural, industrial, recreational and other legitimate beneficial uses; to provide for the prevention, abatement and control of new or existing water pollution";

335-6-10-.06 Minimum Conditions Applicable to All State Waters. (c) State waters shall be free from substances attributable to sewage, industrial wastes or other wastes in concentrations or combinations which are toxic or harmful to human, animal or aquatic life to the extent commensurate with the designated usage of such waters.

Antidegradation Policy
Use of biocriteria or bioassessment not included in antidegradation policy.

Biological Assessment

What biological assemblages are used in the bioassessment program?
Benthic macroinvertebrates and fish are fully developed. Periphyton is under development, but used to support nutrient TMDLs.

Are bioassessments used to support 303(d) listings?
Yes. Listing methodology: Alabama’s Water Quality Assessment and Listing Methodology 2020 (PDF) (16 pp, 562 K)

4.8.6 Use of Biological Assessments
Biological assessments compare data from biological surveys and other direct measurements of resident biota in surface waters to established biological criteria and assess the waterbody’s degree of use support. Alabama has not established numeric biological criteria (except in the case of chlorophyll a in reservoirs) and, as a result, biological data are used as a means of applying narrative criteria contained in Alabama’s water quality criteria document (ADEM Administrative Code Chapter 335-6-10).

How are assemblages used to make impairment decisions?
Alabama has added fish as a second assemblage in the 2016 CALM. To date, the assemblages have been surveyed at separate sites to allow ADEM to increase the number of sites assessed. The assemblage to be surveyed at each site is determined on location in a Strategic Habitat Unit (fish), drainage area and average depth.

Other uses of biocriteria or bioassessment within the water quality program:
Refining ALU, 305(b) surface water condition assessments, TMDL development and assessment, non-point source assessments, BMP evaluation, and restoration goals

Technical Support Information and Documents:

Reference condition:
Landuse and other watershed factors are evaluated to identify candidate reference reaches (using ADEM’s measure of watershed disturbance); criteria of “least-disturbed” specified by Level 4 ecoregion and drainage area; watershed and reach then reconned to survey for obvious impacts and disturbances; candidate ref reaches then sampled intensively for one year; data reviewed to verify RR status; data used to characterize biological, chemical, and physical habitat.   

Technical reference material:
  • Midwest Biodiversity Institute (MBI). 2019. Refining State Water Quality Monitoring Programs and Aquatic Life Uses: Evaluation of the Alabama DEM Bioassessment Program. MBI Technical Memorandum MBI/2015-12-10. Submitted to Alabama Dept. of Environmental Management, Montgomery, AL. 48 pp. + appendices
  • Wadeable rivers and streams:
    • OAW: narrative rating of Good or higher, using ADEM’s macroinvertebrate or fish community surveys
    • S, PWS, F&W: narrative rating of Fair or higher, using ADEM’s macroinvertebrate or fish community surveys
    • LWF and A&I streams: none
  • Nonwadeable reservoirs:
    • Numeric criteria based on chl a (response variable to nutrient enrichment)
Stressor identification/causal analysis approach:
  • Concomitant monitoring for biota, water quality, habitat
  • Follow-up monitoring conducted if necessary
  • Using these data to refine response signatures, and other information

Technical reference material:
2020 Integrated Water Quality Monitoring and Assessment Report (PDF)(630 pp, 26 MB)

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