40 CFR s. 130.7 Total maximum daily loads (TMDLs) and individual water quality-based effluent limitations. This section provides additional information related to requirements for developing the impaired waters list.
40 CFR s. 130.8 Water Quality Reports. States must submit water quality reports to EPA that include a water quality assessment of state waters.
40 CFR s. 130.3. Water quality standards. This section defines water quality standards as setting water quality goals for a waterbody that will protect its designated uses (such as protection of fish, wildlife, recreation, and public health and welfare). Criteria will be set to protect those uses.
40 CFR s. 131.11 Criteria. States must adopt those water quality criteria that protect the designated use. Such criteria must be based on sound scientific rationale and must contain sufficient parameters or constituents to protect the designated use. For waters with multiple use designations, the criteria shall support the most sensitive use. 7. Comparison with Similar Rules in Adjacent States:
All states follow assessment procedures similar to the department’s general waterbody assessment procedures outlined in subch. III of ch. NR 102, Wis. Adm. Code.
Biological assessments are used by states to evaluate the biological health of surface waters and the results of assessments are summarized in biennial reports that are submitted to U.S. EPA. Some states assess waterbodies through guidance and other states have established narrative or numeric biological thresholds or criteria in rules. Narrative biological assessment thresholds provide a general statement of goals and the types of metrics that an agency uses to evaluate the biological health (quality of fish, insects, plants, or other aquatic life) of a waterbody, while numeric biological assessment thresholds specify numeric benchmarks that an agency uses to evaluate a waterbody’s biological health. Wisconsin is proposing both narrative and numeric biological assessment thresholds. Under Wisconsin’s proposed structure, these will be part of the state’s assessment protocols but will not be considered water quality criteria, as they are in some other states. Indiana currently has narrative biocriteria. Until recently, Minnesota had narrative biocriteria but recently revised their biocriteria to a numeric format. Ohio also has promulgated numeric biocriteria. Michigan, Illinois, and Iowa have not formally incorporated narrative or numeric biocriteria into their water quality standards. However, all Region 5 states, Iowa, and most other states in the nation do use biological metrics such as fish and insect scores for waterbody assessments and section 303 (d) listing, regardless of whether narrative or numeric thresholds or biocriteria are codified. Pursuant to 33 USC s. 1315, states are required to report on the biological health of surface waters every two years.
Most Region 5 states use some variation on phosphorus response indicators, including algal indicators or criteria. Minnesota has a promulgated combined criteria approach to assessing nutrient levels and their biological and chemical responses. Minnesota’s biological metrics center on chlorophyll a. Ohio’s approach is to use a multi-metric scoring system that aggregates results from separate evaluations of primary productivity (algae/plants), biological health and in-stream nutrient concentrations. Indiana has a process for assessing phosphorus impairments using chlorophyll a response indicators. Illinois has numeric phosphorus criteria for lakes and is currently considering promulgating proposed numeric phosphorus criteria for streams/rivers. Illinois also has narrative nutrient criteria and considers a water to be not meeting the criteria if excess algae is present in the waterbody. Michigan does not currently have numeric phosphorus criteria, but does have narrative phosphorus criteria. Iowa does not currently have phosphorus criteria but does assess waterbodies for phosphorus and chlorophyll a, and uses chlorophyll a to list waters as impaired for eutrophication based on narrative criteria.
Wisconsin, Minnesota, Michigan and Indiana are the main states in EPA Region 5 that have two-story fishery lakes supporting coldwater fish. Wisconsin’s oxythermal criteria were developed using a modification of methods developed in Minnesota. Although Minnesota uses its methods for assessments, it has not yet codified oxythermal criteria for its two-story fishery lakes. Minnesota and Indiana have general dissolved oxygen and temperature criteria for cold waters, though they do not distinguish between lakes and streams. Michigan has dissolved oxygen criteria specific to lakes with coldwater fish. These criteria generally require maintenance of at least 7 mg/L dissolved oxygen within the lake at varying depths, depending on certain lake characteristics. Michigan’s temperature criteria for all inland lakes also apply to coldwater lakes and, among other provisions, do not allow decreases in the volume of the thermocline/hypolimnion.8. Summary of Factual Data and Analytical Methodologies Used and How Any Related Findings Support the Regulatory Approach Chosen:
All of the biological metrics included in this rule package are based on detailed analysis of Wisconsin data, as well as review of relevant literature, EPA recommendations, and approaches used in other states. These analyses are described in a technical support document for the rule. The Waterbody Assessments subchapter in this rule package outlines the types of biological assessments done by the department to assess a waterbody’s fish, aquatic insect, aquatic plant, and algae communities. These metrics are based on published scientific papers and are standard methods used and refined by the department over time.
The oxythermal habitat criteria were newly developed as part of this rule package based on a modification of a method used in Minnesota, and was also recently published as a scientific paper.
The algal metrics for recreation were developed using statistical analysis of Wisconsin lake user perception surveys.
The suspended chlorophyll a assessment threshold for aquatic life are based on trophic status to prevent a waterbody from becoming algal dominated and impairing feeding and reproduction of fish and insects.
The aquatic plant threshold for lakes was developed based on Wisconsin lake data and was recently published as a scientific paper.
The stream benthic algae phosphorus response indicator is based on relationships between the occurrence of diatom taxa and phosphorus concentrations. After initial recommendations for this rule were developed, an external stakeholder committee met periodically over the course of two years to review the recommendations and provide feedback, and additional information was provided throughout this process. EPA water quality standards staff were part of this committee and also provided technical input.
9. Analysis and Supporting Documents Used to Determine the Effect on Small Business or in Preparation of an Economic Impact Report:
This rule primarily pertains to biological assessments of surface waters. The department expects this rule package to have minimal economic impacts, for two main reasons:
1.
This rule largely documents protocols and procedures already used by the department for standard assessments. These types of assessments are common among Region 5 and other states. Because it largely reflects the status-quo for waterbody assessments, additional costs are not anticipated.2.
Biological assessment thresholds are not expected to have direct impacts on the regulated community. Rather, they help the department determine what types of stressors may be affecting biological communities, and whether restoration actions may be needed to mitigate those stressors. In the rare case where a waterbody achieves the water quality criterion for a pollutant, but the biological community is degraded and the department determines through further research that the pollutant is causing or contributing to the biological degradation, the department could only develop a more protective site-specific criterion for the pollutant in that waterbody through rulemaking. Outside of that process, biological assessments do not affect permit limits.Waterbody assessments and reporting. The first portion of this proposed subchapter provides a general outline of the types of waterbody assessments currently being used by the department as required under the Clean Water Act. As such, there is no economic impact expected from the creation of these sections.
Biological assessment thresholds. This rule incorporates both narrative and numeric biological assessment thresholds. These are described individually below, and neither type of assessment is expected to have an economic impact. The following information about how these thresholds are applied is pertinent to both narrative and numeric assessment thresholds:
The department’s guidance for assessing waterbodies, Wisconsin Consolidated Assessment and Listing Methodology guidance or WisCALM, has additional detail on recommended goals and methods for biological assessment thresholds (both numeric and narrative). WisCALM guidance has been used by the department for years to prepare the biennial surface water quality report required under 33 USC 1315 that is submitted to U.S. EPA. It will continue to be used and updated every two years in preparation for the biennial report, and any updates to the guidance are subject to a separate public notice and comment period. As WisCALM is updated over time, existing biological metrics such as those for fish and aquatic insects may be revised to reflect the most recent science and public input. If any new biological metrics are included in WisCALM in the future, waterbodies would then be assessed for attainment of the new biological metric as well. However, the proposed numeric assessment thresholds, once established in rule, may only be revised through future rulemaking.
Under any biological assessment thresholds—narrative or numeric--a waterbody that is determined to be biologically degraded (listed as having “observed effects”) and for which a pollutant is identified as the cause of the degradation may be subject to future pollutant reduction measures that could entail a cost. However, permitted dischargers would only be fiscally impacted if a site-specific criterion (SSC) more stringent than the pollutant’s statewide criterion was developed by rule and approved by U.S. EPA. Development of such SSC through rulemaking is already allowable under existing authority.Narrative biological assessment thresholds. This section establishes narrative biological assessment thresholds that describe the biological quality goals for a surface water’s aquatic life community, and provides a general outline of the procedures currently being used by the department to assess biological quality. As such, there is no economic impact expected from the creation of this section. WisCALM guidance recommendations will be used in interpreting narrative thresholds—for instance for fish and aquatic insect assessments that are not codified—but as guidance these recommendations are non-binding and subject to change.
Numeric biological assessment thresholds for lakes, reservoirs, and impounded flowing waters.
Aquatic plant numeric assessment thresholds. Aquatic plant numeric thresholds established in this rule identify lakes or reservoirs in which the plant community has been degraded due to a variety of disturbance factors. This metric was added in response to stakeholder preferences to include numeric thresholds. As a biological assessment threshold, this metric would not affect permit limits. As with other biological thresholds, if a lake is not attaining these thresholds it would be listed as having “observed effects” on the section 303(d) list.
Algae (chlorophyll a) numeric assessment thresholds to determine attainment of Recreation and Aquatic Life uses. These numeric thresholds apply to lakes, reservoirs and impounded flowing waters and are the same as algae levels already considered by the department to assess water quality for the biennial report to U.S. EPA and used to list a waterbody as impaired when its uses are adversely affected. The department’s analysis shows that, once attained, the existing statewide phosphorus criteria will be protective of the proposed chlorophyll a assessment thresholds in most waterbodies. The department does not intend to require chlorophyll a monitoring of discharges, and there are no permit implementation procedures associated with the chlorophyll a standard included in this rule package. The only way a more stringent phosphorus limit would be derived based on an exceedance of a chlorophyll a assessment threshold is if a more-stringent phosphorus SSC was developed by the department through rulemaking and approved by U.S. EPA. Any potential costs associated with a more stringent SSC would be evaluated as part of that rulemaking process. The establishment of chlorophyll a assessment thresholds does not provide any new authority for developing SSC; that avenue is already available where algae levels are a concern. For these reasons, the department does not expect an additional economic impact based on this change. Phosphorus assessment procedures using biological metrics. These sections clarify the protocols currently used by the department to assess attainment of the phosphorus criteria, and add a component that allows a waterbody’s biological response to phosphorus, or lack thereof, to be taken into account before listing it as impaired for phosphorus. This will provide the benefit of keeping a small number of waters off the impaired waters list that have healthy biological communities, but which may have periodic exceedances of the phosphorus statewide criterion. It would not add additional waters to the impaired waters list. No costs are associated with this portion of the rule.
Dissolved oxygen criteria for Aquatic Life. Revisions to the dissolved oxygen section are minimal and help clarify which criteria apply to different waterbody types. These have no expected economic impact. The addition of oxythermal criteria for two-story fisheries is useful in assessing the health of the fishery but is not expected to have an economic impact, as there are no dischargers with individual Wisconsin Pollutant Discharge Elimination System (WPDES) permits on or upstream of two-story fishery lakes. If a waterbody is not attaining this criterion, the department may recommend a study to determine the reason for non-attainment and what restoration actions may be appropriate.
NR 217 calculation of upstream background phosphorus concentrations. The department does not anticipate an economic impact from this revision. Currently, the two methods yield very similar results and alignment of the calculation methods is not expected to have an impact. For a small number of facilities it is possible that this would change the upstream phosphorus concentration used and the resulting calculated limit, but this minor change would not necessitate different treatment types, and economic impacts are not expected.
Definitions. Because the clarifications to definitions are not expected to change the waterbodies included in the categories, only clarify existing interpretation of these terms, no economic impact is expected.
10. Effect on Small Business (initial regulatory flexibility analysis): As discussed above, this rule is not expected to incur additional costs for small businesses.
11. Agency Contact Person: Kristi Minahan, Wisconsin Department of Natural Resources, Bureau of Water Quality WY/3, P.O. Box 7921, Madison, WI 53707-7921;
12. Place where comments are to be submitted and deadline for submission:
RULE TEXT
Section 1 NR 102.03 (intro.) is amended to read:
NR 102.03 Definitions. In this chapter, the following definitions are applicable to terms usedapply:
Section 2 NR 102.03 (1c), (1e), (1g), (1i), (1k), (1m), (1q), (1v), and (6)(6d), and (9) are created to read:
NR 102.03 (1c) “Benthic” means relating to the ecological zone at the bottom of a body of water, including the sediment surface and subsurface layers.
(1e) “Biocriterion” means a surface water quality criterion under subch. III that describes the structure and function of aquatic communities in a waterbody necessary to protect its designated aquatic life use. “Biological assessment threshold” means a numeric value or condition description used to measure the quality of a waterbody’s biological community and to determine attainment of its designated uses.
(1g) “Chlorophyll a” means a green pigment present in all green plants and in cyanobacteria, responsible for the absorption of light to provide energy for photosynthesis.
(1i) “Clean Water Act” means the federal Clean Water Act of 1972 and amendments.
(1k) “Confidence interval” means a range within which the true value of a parameter is likely to occur, with a specified level of confidence.
(1m) “Diatom” means a common and diverse group of unicellular algae of the phylum Chrysophyta, having cell walls containing silica.
(1q) “Impounded flowing water” means a waterbody impounded by a constructed outlet structure on a river or stream that is not a reservoir as defined in sub. (4m).
(1v) “Macrophyte” means an aquatic plant large enough to be seen without the use of a microscope.
(6d)(6) “Section 303 (d) list” means a list of waters that do not attain water quality standards and require a total maximum daily load analysis, as specified under section 303 (d) of the Clean Water Act, 33 USC 1313 (d). (9) “U.S. EPA” means the United States environmental protection agency.
Section 3 NR 102.04 (4) (a) is repealed and recreated to read:
NR 102.04 (4) (a) Dissolved oxygen. 1. For streams, rivers, and impounded flowing waters, dissolved oxygen criteria apply to samples taken from the main channel near the area with greatest flow. For lakes or reservoirs, the dissolved oxygen criteria in this paragraph apply to the epilimnion of stratified lakes and to all but the deepest one meter of the water column of unstratified lakes.
2. Except as provided in subds. 3. to 7. and par. (am), surface waters shall attain a minimum dissolved oxygen concentration of 5 mg/L at all times.
3. A waterbody classified by the department as a trout class I or II water under s. NR 1.02 (7), a cold water community that is not a two-story fishery lake covered under par. (am), or a great lakes tributary used by salmonids for spawning during the period of habitation, shall attain all of the following: a. A minimum dissolved oxygen concentration of 6.0 mg/L at all times.
b. A minimum dissolved oxygen concentration of 7.0 mg/L when cold water fish are spawning through fry emergence from their redds, or gravel nests.
Note: The period from spawning through fry emergence from their gravel nests is approximately mid-October through April, but varies depending on water temperature and location in the state.
c. Dissolved oxygen concentrations and diurnal patterns may not be altered from natural background levels to such an extent that cold water populations are adversely affected.
4. A waterbody classified by the department as trout class III under s. NR 1.02 (7) shall attain a minimum dissolved oxygen concentration of 6.0 mg/L at all times. 5. A waterbody for which a use attainability analysis under 40 CFR 131.10 (g) (1) to (6) demonstrates that its otherwise applicable designated use category is unattainable shall attain the following: a. For a coldwater community with an approved use attainability analysis, a minimum dissolved oxygen concentration of 5 mg/L at all times.
b. For any other community, a minimum dissolved oxygen concentration of 3 mg/L at all times.
Note: Waterbodies described in subd. 5 are also known as altered warmwater or altered macroinvertebrate waters.
