The Wisconsin Natural Resources Board adopts an order to repeal NR 210.06 (4) to (6); to renumber NR 102.03 (6); to amend NR 102.04 (5) (a), 104.06 (2) (a) (intro.) and (b) (intro.), 104.20 (7), and 210.06 (2) (intro.) and (7); to repeal and recreate NR 102.04 (6), 210.06 (2) (a), 219.04 Table A and table notes 1 to 33, Table EM header row 2, parameters “Fecal Coliform”, “Salmonella” (including sub-rows), and “Dioxins and Furans” and table notes 8 and 11, and Table H and table notes 1 to 33; and to create NR 102.03 (9), 210.06 (1) (title), (2) (title), (b) (title) and (Note 2), and (3) (title), and 219.04 Table EM table notes 16 to 23 relating to updating Wisconsin’s water quality criteria for pathogens, specifically bacteria, to protect recreational uses; and updating related WPDES permit implementation procedures for the revised water quality standards to be consistent with EPA’s recreational water quality criteria, and affecting small business.
Analysis Prepared by the Department of Natural Resources
1. Statute Interpreted:
Sections 281.15, 283.13, and 283.31, Wis. Stats.
2. Statutory Authority:
Sections 281.12, 281.13, 281.15, 283.13, 283.31, 283.37, 283.55, 283.83, and 227.11, Wis. Stats.
3. Explanation of Agency Authority:
Revisions to the recreational use, updated recreational water quality criteria, and newly developed impaired waters listing protocols will be promulgated pursuant to ss. 281.12, 281.13, and 281.15, Wis. Stats.:
Section 281.12, Wis. Stats., grants the department general supervision and control to carry out the planning, management, and regulatory programs necessary for prevention/reduction of water pollution and for improvement of water quality.
Sections 281.13(1)(a) and (b), Wis. Stats., grant the department the authority to create rules to research and assess water quality in the state.
Section 281.15, Wis. Stats., mandates that the department promulgate water quality standards, including water quality criteria and designated uses. It recognizes that different use categories and criteria are appropriate for different types of waterbodies, and that the department shall establish criteria which are not more stringent than reasonably necessary to ensure attainment of the designated use for the waterbodies in question.
The Wisconsin Pollutant Discharge Elimination System (WPDES) permit program procedures to implement the revised standards will be promulgated under the following authority:
Section 283.13(5), Wis. Stats., states that the department shall establish more stringent limitations than required under subs. 283.13(2) and (4), Wis. Stats., when necessary to comply with water quality standards.
Section 283.31(3) and (4), Wis. Stats., state that the department may issue a permit upon condition that the permit contains limitations necessary to comply with any applicable federal law or regulation, state water quality standards, and total maximum daily loads.
Section 283.37, Wis. Stats., grants the department authority to promulgate rules regarding permit applications.
Section 283.55, Wis. Stats., grants the department authority to impose monitoring and reporting requirements.
Section 283.83, Wis. Stats., requires the department to establish a continuing planning process and that plans shall include implementation procedures including compliance schedule for revised water quality standards.
Section 227.11(2), Wis. Stats., grants the department authority to promulgate rules that are necessary to administer the specific statutory directives in ch. 283, Wis. Stats.
4. Related Statutes or Rules:
These rules relate to surface water quality standards and the WPDES permit program. Related rules include chs. NR 102 and 104, Wis. Adm. Code, which comprise Wisconsin’s surface water quality standards, and chs. NR 200 to 299, Wis. Adm. Code., which comprise the WPDES permit program.
5. Plain Language Analysis:
The Clean Water Act (CWA) requires states to adopt water quality standards to protect recreation in and on the water. Water quality standards include a recreation designated use and water quality criteria that protect this use. In addition to the CWA requirements, the Beaches Environmental Assessment and Coastal Health (BEACH) Act requires states with coastal waters (e.g., the Great Lakes) to adopt new or revised criteria for pathogens (including bacteria) to protect recreation not later than three years after the United States Environmental Protection Agency (EPA) publishes revised criteria to maintain eligibility for grant funding for communities. The EPA published revised national recommended recreation water quality criteria for bacteria in 2012.
Human waste contains a number of pathogens that can be spread through water and cause a wide range of diseases. The EPA employs the pathogen indicator concept for these criteria in which the indicator does not itself cause disease, but instead signals the potential for illness caused by human fecal contamination. Pathogen indicators, such as certain bacteria, are used because they tend to be more numerous than pathogens in human fecal matter and are cheaper, safer, and easier to measure. In their 2012 recommended criteria, EPA provides a choice for states to use either E. coli or enterococci as their pathogen indicator.
The goals of this rule package are to adequately protect the public while recreating in and on Wisconsin’s waters; revise Wisconsin’s bacteria water quality criteria to be consistent with EPA’s latest recommendations; and update the permit requirements for sewage treatment works to ensure consistency with EPA’s policies. To accomplish these goals, the department proposes to revise the bacteria water quality criteria for recreation in ch. NR 102, Wis. Adm. Code, remove fecal coliform criteria for individual waters from ch. NR 104, Wis. Adm. Code, revise the permit requirements for publicly owned and privately owned domestic sewage treatment works in ch. NR 210, Wis. Adm. Code, and update Tables A, EM, and H, or portions thereof related to bacteria, to incorporate EPA’s most recent approved methods in ch. NR 219, Wis. Adm. Code.
Bacteria Water Quality Criteria for Recreation
In 2012, EPA recommended updates to bacteria criteria and provided states with a choice of criteria for E. coli and enterococci at two different risk levels. The department evaluated the pathogen indicator, risk level, and the frequency and duration of exceedances for assessment determinations. The department also added language to allow for the development of bacteria site-specific criteria and removed the fecal coliform “variance” criteria in ch. NR 104, Wis. Adm. Code.
Pathogen Indicator
EPA provided states two options for their pathogen indicator: E. coli or enterococci. Since the adoption of the BEACH Act in 2004, permittees in Wisconsin and the other Great Lake States have monitored for E. coli in the Great Lakes basin. As such, there is a large amount of data on E. coli levels in the Great Lakes. Additionally, the department has been assessing inland and Great Lakes beaches against EPA’s 1986 E. coli criteria. Given these reasons, the department chose to use E. coli as the pathogen indicator for the revised recreation criteria.
Criteria Magnitude
EPA recommends that states assess for their selected indicator using two methods: the geometric mean (GM) and the statistical threshold value (STV). Use of both methods ensures that states not only assess the average over time with the GM, but also account for the frequency of bacterial level spikes with the STV.
Since 1986, EPA’s recommended bacteria water quality criteria for recreation have consisted of long-term and short-term criteria. In the 1986 recommendations, a GM was used as the long-term criterion and a single sample maximum (SSM) as the short-term criterion. In the 2012 recommendations, the same geometric mean is used as the long-term criterion. However, the recommendations for short-term criteria replace the SSM with a different approach, the STV. The SSM criterion from 1986 set a “do not exceed” threshold which limited the ability to account for natural variation. The 2012 STV criterion corresponds to the 90th percentile of the water quality distribution data. This is intended to allow for occasional, but not frequent, spikes in bacteria levels, reflecting the expected variability in water quality measurements.
Previously, when the department was using fecal coliform as the pathogen indicator, the criterion was only applied as a geometric mean. The revised rule for E. coli contains both GM and STV criteria.
Illness Rate
EPA provided two illness rates for states to choose from: either 32 or 36 cases of gastrointestinal illness out of 1,000 primary contact recreation users. The department selected the criteria based on the higher illness rate of 36 per 1,000 users. The criteria based on the higher illness rate are consistent with the level of protection provided by the EPA’s previous and current criteria recommendations, and EPA concluded that criteria based on either of the illness rates would provide adequate human health protection. Criteria based on the lower illness rate would have been more stringent than criteria based on the higher illness rate. The department evaluated the impact of selecting the lower illness rate on permittees and impaired waters listings. Selecting the lower illness rate would unnecessarily require lower (more stringent) effluent limits for facilities and increase the number of impaired waters and beach advisories without a commensurate decrease in human health risk.
Criteria Duration
A criterion’s duration is the time period over which the criterion is assessed. The department selected a duration of 90 days, which means that samples from throughout a 90-day time period would be used for calculating attainment of the criteria. The duration of 90 days is proposed for both geometric mean and statistical threshold value criteria. It was selected to ensure adequate protection of the recreation designated use and to allow assessment of Wisconsin’s waters in a comprehensive and informative manner. This duration allows the department to assess more waterbodies and allows for a clear evaluation of the waterbody’s impairment status. The 90-day duration is consistent with a white paper produced by EPA clarifying that up to 90 days was determined to be an acceptable and scientifically defensible duration for E. coli criteria (U.S. EPA. 2015. Narrative justification for longer duration period for recreational water quality criteria).
Bacteria Site-Specific Criteria (SSC)
When numeric criteria are established, they must be based on EPA’s recommended water quality criteria, EPA’s recommended water quality criteria modified to reflect site-specific conditions, or other scientifically defensible methods. The EPA must review and approve a state’s criteria and does so only if the criteria are based on sound scientific rationale and contain sufficient parameters to protect the designated use. The EPA recognizes that there are sites where non-human and non-fecal sources may contribute to high bacteria levels while the probability of illness at these sites may be much lower than the probability of illness at sites with human sources. In such cases, the EPA allows for less-stringent site-specific criteria to be established if they are based on sound scientific rationale and contain sufficient parameters to protect the designated use.
Links to Admin. Code and Statutes in this Register are to current versions, which may not be the version that was referred to in the original published document.