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Bioassessment and Biocriteria Program Status for New Mexico: Streams and Wadeable Rivers

State Program Contact

New Mexico Surface Water Quality Bureau Exit

Water Quality Standards

WQS Information
The link to New Mexico's WQS that are in effect for Clean Water Act purposes is provided. These are the WQS approved by EPA.
The state of New Mexico 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
New Mexico’s ALUs are based on thermal definitions and tolerances. They are defined at NMAC. New Mexico also has a Limited ALU designation. This subcategory includes surface waters that support aquatic species selectively adapted to take advantage of naturally occurring rapid environmental changes, ephemeral or intermittent water, high turbidity, fluctuating temperature, low dissolved oxygen content or unique chemical characteristics.

  • High Quality Cold
  • Cold
  • Marginal Cold
  • Cool
  • Warm
  • Marginal Warm Water
  • Limited

Biological Criteria
__X__ Narrative statement
_____ Numeric
_____ No criteria Biological integrity:
Surface waters of the state shall support and maintain a balanced and integrated community of aquatic organisms with species composition, diversity and functional organization comparable to those of natural or minimally impacted water bodies of a similar type and region.

Antidegradation Policy
Use of biocriteria or bioassessments not included in the state's antidegradation policy, NMAC (PDF)(48 pp, 378 K)

Biological Assessment

What biological assemblages are used in the bioassessment program?
Benthic macroinvertebrates, periphyton, diatoms, and fish (Fish Index of Biological Integrity in progress)

Are bioassessments used to support 303(d) listings? 
Yes. Listing methodology: Comprehensive Assessment and Listing Methodology (CALM) (PDF) (43 pp, 692 K) - Section 3

How are assemblages used to make impairment decisions?
Refer to Comprehensive Assessment and Listing Methodology (CALM) (PDF) (43 pp, 692 K) - All are applied independently.

Other uses of biocriteria or bioassessment within the water quality program:
Refining ALU; Sediment and Nutrient assessments are based on stressor-response relationships.

Technical Support Information and Documents:

Reference condition:
New Mexico has used reference sites to develop our benthic macroinvertebrate, sedimentation, and nutrient assessment protocols, all available at Comprehensive Assessment and Listing Methodology (CALM) (PDF) (43 pp, 692 K) .

Technical reference material:

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:

Stressor identification/causal analysis approach:
Concurrent monitoring for biota and stressors. Probable source determination included in assessment protocol.

Technical reference material:
Assessment Protocol, Field Sampling Plans, Standard Operating Procedures

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