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

State Program Contact

Utah Division of Water Quality Exit

Water Quality Standards

WQS Information
The link to Utah's WQS that are in effect for Clean Water Act purposes is provided. These are the WQS approved by EPA.
The state of Utah 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
ALUs: Cold, warm water, and nongame fishes, and other aquatic life, including the necessary organisms in their food chain. Waterfowl, shorebirds, and other water-oriented wildlife, including necessary organisms in their food chain.

Because the biocriteria are framed in the narrative water quality standards, potentially all described uses in rule may be subject to the biological assessment. Although, assessments are primarily limited to aquatic life uses (Class 3) and waterbodies of the GSL (Class 5). 

Biological Criteria
__X__ Narrative, with quantitative implementation procedures or translators
_____ Numeric
_____ No criteria

R317-2-7.3: Biological Water Quality Assessment and Criteria

Antidegradation Policy
Use of biocriteria or bioassessments not included in antidegradation policy. However, all Tier 1 ADR waters in UT require no discharge.

Biological Assessment

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

Are bioassessments used to support 303(d) listings?
Yes. Listing Methodology: 2020 Integrated Report Assessment Methods (PDF) (112 pp, 4 MB)

How are assemblages used to make impairment decisions?
Benthic macroinvertebrates are the only formal assessment assemblage. The other indicators have been used on site-specific instances. Fish may be used as a biological endpoint in order to determine whether a waterbody is meeting the existing use for delisting purposes.

Other uses of biocriteria or bioassessment within the water quality program:
TMDL development and assessment, non-point source assessments, BMP evaluation, 305(b) surface water condition assessments, restoration goals, resource damage assessments, and determining intensified WQ monitoring locations

Technical Support Information and Documents:

Reference condition:
We score all sites at the site and watershed scale for reference condition and also combine that score with an independent best professional judgment validation.

Development of biocriteria involves the collection and interpretation of biological data –e.g. benthic macroinvertebrates, fish, and periphyton. During this process entities typically use biological metrics (usually aggregated into a multimetric index) and/or multivariate analysis to assess whether a waterbody is meeting its designated aquatic life use(s). The reference materials included below include standard operation procedures used in data collection, compilation, technical approaches used to develop biocriteria as well as its implementation procedures.

Technical reference material: 
Field Manual: Utah’s Comprehensive Assessment of Stream Ecosystems (UCASE) (PDF) (188 pp, 14 MB)
Benthic Macroinvertebrate SOP (PDF) (24 pp, 1 MB)
2020 Integrated Report Assessment Methods (PDF) (112 pp, 4 MB)

Stressor identification/causal analysis approach:
Stressor identification/causal analysis is used on a case-by-case basis in an informal way.

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