An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

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

State Program Contact

Arkansas Department of Environmental Quality Exit

Water Quality Standards

WQS Information
The link to Arkansas' WQS that are in effect for Clean Water Act purposes is provided. These are the WQS approved by EPA.
The state of Arkansas 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

You may need a PDF reader to view some of the files on this page. Refer to EPA’s about PDF page to learn more.

Designated Aquatic Life Uses
Reg. 2.302 Designated Uses (page 3-1)

(A) Extraordinary Resource Waters - This beneficial use is a combination of the chemical, physical and biological characteristics of a waterbody and its watershed which is characterized by scenic beauty, aesthetics, scientific values, broad scope recreation potential and intangible social values. (For specific listings, refer to Appendices A and D)

(B) Ecologically Sensitive Waterbody - This beneficial use identifies segments known to provide habitat within the existing range of threatened, endangered or endemic species of aquatic or semi-aquatic life forms. (For specific listings, refer to Appendices A and D)

(C) Natural and Scenic Waterways - This beneficial use identifies segments which have been legislatively adopted into a state or federal system. (For specific listings, refer to Appendices A and D)

(F) Aquatic Life - This beneficial use provides for the protection and propagation of fish, shellfish and other forms of aquatic biota. It is further subdivided into the following subcategories:

(1) Trout - Water which is suitable for the growth and survival of trout (Family: Salmonidae).

(2) Lakes and Reservoirs - Water which is suitable for the protection and propagation of fish and other forms of aquatic biota adapted to impounded waters.  Generally characterized by a dominance of sunfishes such as bluegill or similar species, black basses and crappie. May include substantial populations of catfishes such as channel, blue and flathead catfish and commercial fishes including carp, buffalo and suckers.  Forage fishes are normally shad or various species of minnows. Unique populations of walleye, striped bass and/or trout may also exist.

(3) Streams - Water which is suitable for the protection and propagation of fish and other forms of aquatic biota adapted to flowing water systems whether or not the flow is perennial. Specific designated use attributes and key species are described for each ecoregion (refer to Reg 2.302 Designated Uses)

Biological Criteria
__X__ Narrative statement
_____ Numeric
_____ No criteria

Reg. 2.405 Biological Integrity (page 4-2)
For all waters with specific aquatic life use designated in Appendix A, aquatic biota should not be impacted. Aquatic biota should be representative of streams that have the ability to support the designated fishery, taking into consideration the seasonal and natural variability of the aquatic biota community under naturally varying habitat and hydrological conditions; the technical and economic feasibility of the options available to address the relevant conditions; and other factors.

An aquatic biota assessment should compare biota communities that are similar in habitat and hydrologic condition, based upon either an in-stream study including an upstream and downstream comparison, a comparison to a reference water body within the same ecoregion, or a comparison to community characteristics from a composite of reference waters. Such a comparison should consider the seasonal and natural variability of the aquatic biota community. It is the responsibility of the Department to evaluate the data for an aquatic biota assessment to protect aquatic life uses designated in Appendix A. Such data may be used to develop permit effluent limitations or conditions.

Antidegradation Policy
Chapter 2 of Regulation 2 (page 2-1)
ADEQ assesses biological assemblages (fish and macroinvertebrates) to evaluate designated use attainment (Reg. 2.302F, Assessment Methodology 5.0 Biological Integrity). Historically, evaluation of aquatic life designated uses were for special projects or to assess impaired waters. In spring 2016, ADEQ initiated a cyclical ambient biological monitoring network that allows for continued monitoring and evaluation of existing uses. Continued long-term physical, chemical, and biological monitoring will allow ADEQ to determine what, if any, degradation has occurred over time.

Biological Assessment

What biological assemblages are used in the bioassessment program?
Benthic macroinvertebrates, fish, and periphyton

Are bioassessments used to support 303(d) listings?
Yes. Listing methodology: 2018 Integrated Water Quality Monitoring and Assessment Report (PDF) (78 pp, 2 MB)

How are assemblages used to make impairment decisions? 
Biological integrity is evaluated using macroinvertebrate and/or fish communities collected within the waterbody. At a minimum, paired biological and physical data must be collected over two seasons using methods outlined in a Quality Assurance Project Plan with requirements equal to or more stringent than that of ADEQ or USGS. Chemical data for biological integrity analysis should be collected as per methods outlined within Section 6.1 - 6.12 of this document. Results from acute and chronic toxicity tests of vertebrates and invertebrates will also be evaluated, when available, but are not required to make a use determination.

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

Technical Support Information and Documents:

Reference condition:
ADEQ is currently developing a spatial tool that utilizes GIS to analyze and categorize LULC variables, which ultimately will identify disturbance gradients across water quality monitoring stations. 

Not available.

Stressor identification/causal analysis approach:
Not applicable.

Top of Page