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

State Program Contact

Water Quality in Indiana Exit

Water Quality Standards

WQS Information
The link to Indiana's WQS that are in effect for Clean Water Act purposes is provided. These are the WQS approved by EPA.
The state of Indiana 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
Warmwater vs. cold-water ALU designations in state water quality standards

  • Well-balanced warm water aquatic community
  • Cold-water put-and-take trout waters

Biological Criteria
_____ Narrative
_____ Numeric
__X__ No criteria

Antidegradation Policy
327 IAC 2-1.3-5 Antidegradation Standards and Implementation Procedures

Biological Assessment

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

Are bioassessments used to support 303(d) listings?
Yes. Listing methodology: IDEM’s Consolidated Assessment and Listing Methodology (CALM)

How are assemblages used to make impairment decisions?
Independently applied.

Other uses of biocriteria or bioassessment within the water quality program:
TMDL development and assessment, antidegradation, non-point source assessments, BMP evaluation, 305(b) surface water condition assessments, and evaluation of discharge permit conditions

Technical Support Information and Documents:

Reference condition:
The primary filter used in selecting reference sites is land use criteria such as percent of agricultural or urban areas, impervious surface area, human population density and distribution, road density and crossings, proportion of active mining activities, proportion of protected lands, and proximity to permitted facilities, confined feeding operations, and Superfund sites. IDEM provided Tetra Tech with 1458 sites previously sampled for fish and/or macroinvertebrates between 2003 and 2013 for possible reference site selection.  Using land use factors as the primary filter, Tetra Tech provided a list of 324 reference sites. IDEM narrowed down the list further by using in-stream chemical and physical data as a secondary filter. In altered watersheds, chemical and in-stream physical habitat data may be used as a secondary filter to select reference sites and develop biological expectations for “least disturbed condition” (best available condition given widespread disturbance). Based on the spatial distribution of the sites and available resources, IDEM will conduct site reconnaissance and sampling of reference sites with the goal of at least 20 reference sites each year over the next 10 years to refine biological indices, water quality criteria, and possibly develop other assessment indicators and thresholds.

Currently, the deviation from central tendencies on multimetric indices and the qualitative habitat evaluation index (QHEI) is taken into consideration when evaluating impairment. Field chemistry is measured and sites are sampled for broad chemical analysis.

Indiana has not adopted numeric or narrative biocriteria. However, IDEM uses informal numeric procedures for assessment and listing.

IDEM uses informal numeric procedures, refer to IDEM’s Consolidated Assessment and Listing Methodology (CALM)

Stressor identification/causal analysis approach:
IDEM developed Tolerance Indicator Values for chemical parameters using fish community data and uses Nonmetric Multidimensional Scaling (NMDS) to analyze stress-response relationships between fish data and chemical/physical data; macroinvertebrate communities, however, have not been investigated for biological response signatures.

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