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Rule 57 Water Quality Values

An EGLE contractor stands on the bank of a small culvert, using a long pole (dip pole) to obtain a surface water sample
Environment, Great Lakes, and Energy

Rule 57 Water Quality Values

Rule 57 gives narrative procedures for calculating water quality values for toxic substances to protect humans, wildlife, and aquatic life, in keeping with the federal Guidance.  These values apply to all surface waters in Michigan unless site specific values have been derived.

Michigan's incorporation of a narrative process for developing water quality values within the Water Quality Standards, in keeping with federal guidance, allows the state to use a standardized, transparent process to develop and update water quality values when new toxicological data are available. The ability to routinely update water quality values when new toxicological data are available allows for final values to be developed using a more complete data set with reduced uncertainty in the values.

 

Statewide Rule 57 Water Quality Values

The following are instructions for Interpreting the Rule 57 Water Quality Values Spreadsheet:

Using Rule 57, the following values are determined:

  • Human Noncancer Value (HNV): “drink” and “non-drink”
  • Human Cancer Value (HCV): “drink” and “non-drink”
  • Wildlife Value (WV): (calculated only for Bioaccumulative Chemicals of Concern)
  • Final Chronic Value (FCV)
  • Aquatic Maximum Value (AMV)
  • Final Acute Value (FAV)

The above terms and their uses are defined in the Part 4 Rules.  The use of these values to assess point source discharges and venting groundwater is described in the Part 8 Rules, Water Quality-Based Effluent Limits for Toxic Substances of the NREPA.  Within the Rule 57 Water Quality Values spreadsheet, the identification of a value as “drink” or “non-drink” refers to whether or not a surface water body is designated and protected as a source for a public drinking water supply (See Rule 100 [R 323.1100] – Designated Uses, of the Part 4 Rules).

The following are links to statewide and site-specific Rule 57 water quality values that have been derived for the state of Michigan.  Due to the complexity of the equation used to derive aquatic life values for ammonia, a link is provided to tables showing what the ammonia aquatic life values would be at different temperatures and pHs.

Each chemical is identified by a Chemical Abstract Service number (CAS#) and each Rule 57 water quality value has a Tier status associated with it (Tier 1 or Tier 2) and the year the value was verified.  Tier 1 values are calculated using an optimal set of toxicological data while Tier 2 values are calculated using a lesser amount of data (see Rule 57 for further description of tier designation).  The verification date refers to the year the water quality value was approved for entry into the spreadsheet.

If a substance is not listed in the spreadsheet or if a value is identified with an “ID” (insufficient data) or “NLS” (no literature search), then final values have not been derived. 

A lush riverbank where a water quality sample was obtained

Ammonia

The toxicity of ammonia to aquatic life is pH- and temperature-dependent; therefore, the Rule 57 aquatic life values are equation-based. Equations for calculating the aquatic life values for total ammonia are provided below the Rule 57 table.

Due to the complexity of these equations, the following tables are provided to facilitate the determination of aquatic life values at various pHs (6.5-9) and temperatures (0-30°C).

Ammonia aquatic life value tables

Procedure for Updating Statewide Rule 57 Water Quality Values

 In fiscal year (FY) 2024, a revised procedure for prioritizing routine updates to published Rule 57 values was implemented. The key principle in the procedure is to prioritize chemicals with the highest potential human health or aquatic life impacts (i.e., highest hazard) as well as chemicals with high frequency of occurrence and/or relevance within EGLE’s water quality-based permitting processes. Four criteria associated with the current Rule 57 values are utilized in determining priority:

  1. Chemical hazard classification using the Globally Harmonized System framework.
  2. EGLE, Water Resources Division (WRD), priorities.
  3. Last Review Date (LRD), which is the year the chemical was last reviewed.
  4. Rule 57 assessment tier, which reflects available chemical data when last reviewed.

Separate prioritization lists are developed for Rule 57 human health values and aquatic life values.

It is the intent to use this prioritization procedure to determine which Rule 57 chemicals are to be reviewed in each fiscal year. The review process consists of identifying any new scientific literature for the selected Rule 57 chemical and determining if such new data supports a revision to the currently published Rule 57 values. If prior Rule 57 values are still acceptable, the LRD for the target chemical will be updated to reflect that year that the review was performed.

For development of novel Rule 57 values, selected chemicals are based on review of current scientific literature as well as EGLE, WRD, priorities.

The Rule 57 Water Quality Values Spreadsheet will be updated, as necessary, to include new or revised values.

Three EGLE staff on a small boat conducting electrofishing using specialized equipment to gather fish to sample and help assess water quality

Exceptions to the procedure

An exception to this prioritization procedure may occur if new data for a specific chemical becomes available that suggests the current Rule 57 values represent a significant risk to either aquatic life or human health, then such chemical may be subject to an updated review ahead of its overall prioritization score.

Site-specific Rule 57 Water Quality Values

R 323.1057(2)(r) of the Part 4 Rules gives procedures for deriving site-specific aquatic life values that reflect local environmental conditions. 

The following documents contain the site-specific aquatic life water quality values that have been derived for copper for select streams in the Upper Peninsula of Michigan, and supplemental information used in deriving criteria.

Contact us

Kevin Cox at CoxK12@Michigan.gov or 517-388-6961.

History of the Rule 57 Water Quality Values

On March 23, 1995, the United States Environmental Protection Agency (U.S. EPA) issued the Final Water Quality Guidance for the Great Lakes System (Guidance).  The Guidance instructs Great Lakes states and tribes to use the criteria, methods, policies, and procedures within to establish consistent, long-term protection for water quality in the Great Lakes and their tributaries.  While the Guidance contained specific water quality criteria for certain pollutants, importantly it also included detailed methods to develop criteria for additional pollutants. 

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) updated the Part 4 Rules, Water Quality Standards, promulgated under Part 31, Water Resources Protection, of the Natural Resources and Environmental Protection Act, 1994 PA 451, as amended (NREPA) to reflect this federal Guidance, including the narrative methods to develop water quality values protective of human health and aquatic life.

On August 2, 2000, the U.S. EPA approved the revisions to Michigan’s Part 4 Rules, including Rule 57 (R 323.1057), Toxic Substances.