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Bioassessment and Biocriteria Program Status for North Dakota: Streams and Wadeable Rivers

State Program Contact

North Dakota Department of Health Exit

Water Quality Standards

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

Since the biological monitoring and assessment program was first implemented, its primary objective has been to provide biological data to assess aquatic life use attainment for Section 305(b) reporting and Section 303(d) listing purposes. Biological monitoring data are also used to identify water quality problems and to evaluate the effectiveness of pollution control and abatement programs (e.g., NDPDES, Section 319).

The monitoring objectives of this program are to develop biological indicators using fish, macroinvertebrates and/or periphyton and to use those indicators in biological condition assessments for the state’s rivers and streams at varying spatial scales (e.g., stream reach, watershed, basin, state, ecoregion). Biological monitoring data are also used to identify water quality problems and to evaluate the effectiveness of pollution control and abatement programs (e.g., NDPDES, Section 319).

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Designated Aquatic Life Uses
Fish and aquatic biota. Waters suitable for the propagation and support of fish and other aquatic biota and waters that will not adversely affect wildlife in the area. Low flows or natural physical and chemical conditions in some waters may limit their value for fish propagation or aquatic biota.

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

33-16-02.1-08.2.a. Narrative Biological Goal (PDF)(51 pp, 318 K)
The biological condition of surface waters shall be similar to that of sites or water bodies determined by the department to be regional reference sites.

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, fish, and periphyton

Are bioassessments used to support 303(d) listings? 
Yes. Listing methodology: Water Quality Assessment Methodology for North Dakota’s Surface Waters (PDF) (42 pp, 2 MB)

How are assemblages used to make impairment decisions?
Using the appropriate biological condition and aquatic life use support scoring thresholds for the biological assemblage and ecoregion, an aquatic life use support assessment is made for each sample collected using the following use support decision criteria: 

  • Fully Supporting: Use support assessments for all samples are fully supporting.
  • Fully Supporting, but Threatened: Use support assessment for all samples are fully supporting, but threatened; or Use support assessment for at least one sample is fully supporting, and use support assessments for all other samples are not supporting.
  • Not Supporting: Use support assessments for all samples are not supporting.

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

Technical Support Information and Documents:

Reference condition:
The North Dakota Department of Health (NDDH) utilizes reference (least impaired) and disturbed (most impaired) physical conditions to provide an estimate of natural and human induced variability in biological community structure and in stream habitat quality. Sites are also used to develop threshold values and compile Indices of Biological Integrity (IBI). When selecting reference or disturbed conditions, the NDDH Surface Water Quality Management Program (SWQMP) must account for natural and climatic variability across the state of North Dakota. To account for environmental variability in North Dakota, the state’s total land area was separated into four regions by US Geological Survey Level III Ecoregions and each area was evaluated individually.

The first step in site selection involves a remote sensing component which utilizes an ESRI ArcView Geographic Information System (GIS), ArcView extensions and various GIS data layers. The Analytical Tool Interface for Landscape Assessments (ATtILA) extension allows users to calculate many common landscape metrics including: landscape characteristics, riparian characteristics, human stressors and physical characteristics. Grouped metrics are used to estimate anthropogenic stressors in a 1000 meter (m) circular buffer around distinct sampling points located on perennial flowing waters of the state. Ultimately, a final site score is calculated based on the varying metric scores in the buffer. The most disturbed points are classified with the highest scores while the least disturbed points receive the lowest scores. The highest scoring disturbed sites and lowest scoring reference sites then move to the second evaluation step.

The second screening step is to evaluate each site individually by using additional GIS layers. Sites are plotted and examined for landscape attributes which may result in the site not being suitable for sample collection (e.g. water was too deep). Layers used in screening step two include, but are not limited to, roads, aerial photos, public and private land ownership, township, range and section grids, county boundaries, and dam structures. The remaining viable sampling locations are then evaluated with another level of screening.

The third screening step involves site reconnaissance, also known as ‘ground truthing’. During this step, SWQMP personnel visit sites to evaluate reference or disturbed using best professional judgment. Some important features to consider while ‘ground truthing’ are stream geomorphology, stream habitat alterations (e.g. dams, rip-rap), land use in or adjacent to the riparian zone, and other human influences at or near site locations.

Not available.

Stressor identification/causal analysis approach:
Not applicable.

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