1. (1) Water systems.

   1. (a) General. The water source used to supply a lodging facility shall be a public or a private water system.

   2. (b) Well construction. The operation, construction, installation, materials, and maintenance of the water system used to supply water to the lodging facility shall comply with well construction standards, as enforced by the Wisconsin department of natural resources.

      Note: For more information regarding well construction standards, see ch. NR 812.

   3. (c) Location. Except as provided under par. (d), the private well shall be located on the premises.
   4. (d) Shared private wells. If the operator shares a well that is not located on the premises, the operator shall provide a signed written agreement detailing the physical location of the well and the parties responsible for maintaining the system. _Pf

2. (2) Potable water supply.

   1. (a) Drinking water standards. A lodging facility’s potable water supply shall:

      1. 1. For a public water system, meet the groundwater quality standards in ch. NR 809, as enforced by the Wisconsin department of natural resources. _P

      2. 2. For a private water system, meet the groundwater quality standards in pars. (e) and (f). _P

         Note: For public drinking water well data visit, https://dnr.wisconsin.gov/topic/Groundwater/GRN.html.

   2. (b) Availability. Except as specified under par. (d), each lodging facility shall be provided with a potable water supply under pressure.
   3. (c) Water temperature. Handwashing sinks and fixtures used for bathing shall be equipped to provide water at a temperature of at least 85°F through a mixing valve or combination faucet. _Pf

   4. (d) Temporary water service disruptions. The operator shall inform guests of any water service disruptions to the water supply and shall provide potable water using any one of the following methods _P:

      1. 1. Commercially bottled drinking water.
      2. 2. An enclosed vehicular water tank designed for transporting potable water.
      3. 3. Other methods approved by the department or its agent.

   5. (e) Private well water testing; bacteriological.

      1. 1. The operator shall have bacteriological analysis performed for total coliform and Escherichia coli consistent with approved testing methods pursuant to s. ATCP 77.02 (3). _Pf
      2. 2. Escherichia coli analysis shall not exceed zero colony forming units pursuant to s. NR 140.10. _P
      3. 3. Total coliform analysis shall not exceed zero colony forming units pursuant to s. NR 140.20 (3). _Pf

   6. (f) Private well water testing; nitrates.

      1. 1. The operator shall conduct nitrate analysis consistent with approved testing methods pursuant to s. NR 149.41. _Pf
      2. 2. The analysis of the nitrate concentration in the well water shall not exceed 10 milligrams per liter (mg/L) pursuant to s. NR 140.10. _P
      3. 3. If the analysis of the nitrate concentration in the well water exceeds 10 mg/L, it is considered an unsafe potable water source and the operator shall follow the requirements under par. (h) 3. _P

   7. (g) Private well water testing; frequency, location, approved methods, and notification.

      1. 1. The operator shall test the water from a private well at least once every 12 months from the date that the previous sample was completed. _Pf

         1. a. Bacteriological test results for total coliform that exceed zero colony forming units shall be resampled at a frequency determined by the department. _Pf
         2. b. Continued resampling for bacteriological test results for total coliform that exceed zero colony forming units shall follow the requirements specified in par. (h) 2. _Pf

         Note: A private well sampled in March would have to be sampled again by March 31_st the following year.

      2. 2. The water sample shall be obtained from one of the following:

         1. a. A faucet regularly used by tourists or transients.
         2. b. A sample faucet.
         3. c. An outdoor faucet, if all indoor faucets are made of material that cannot be flamed for disinfection.
      3. 3. Private well water analysis shall be performed by a Wisconsin department of natural resources drinking water certified laboratory or Wisconsin department of agriculture, trade and consumer protection drinking water certified laboratory.

      4. 4. The operator shall notify the department or its agent when:

         1. a. The bacteriological test results for Escherichia coli exceed zero colony forming units as specified in par. (e) 2. _P
         2. b. The bacteriological test results for total coliform exceed zero colony forming units as specified in par. (e) 3. _Pf

         3. c. The nitrate test results exceed 10 mg/L as specified in par. (f) 2. _P

            Note: Bottles for collection of water samples may be obtained by writing to the Wisconsin state laboratory of hygiene, 2601 Agriculture Drive, Madison, WI 53708 or by calling (800) 442 -4618.

            Note: To find a list of Wisconsin department of natural resources drinking water certified laboratories visit https://dnr.wisconsin.gov/topic/labCert/certified-lab-lists.

   8. (h) Unsafe potable water. The operator shall:

      1. 1. Prohibit the use of the entire private water system when bacteriological analysis under par. (e) 2. confirms the presence of Escherichia coli. _P
      2. 2. Discontinue the use of a private water system for drinking water when bacteriological analysis under par. (e) 3., of total coliform is positive on 3 consecutive well water samples and provide an approved water source as required under par. (i). _P
      3. 3. Discontinue the use of a private water system for drinking water and food preparation when nitrate levels exceed the requirements under par. (f) 3. and provide an approved water source as required under par. (i). _P
      4. 4. If required to discontinue the use of the private water system under subd. 2. or 3., the operator shall post signage indicating the water is unsafe for human consumption. _Pf

   9. (i) Alternatives to a private water supply when the use is discontinued for food preparation or drinking water. As required under par. (h) 2. and 3., water for food preparation and drinking shall be provided from any of the following sources:

      1. 1. Commercially sealed water jugs or commercially sealed bottled water provided to the guest upon check-in. _P
      2. 2. Obtained from or contracted with a licensed water distribution service pursuant to ch. ATCP 70. _P

3. (3) Waterborne diseases.

   1. (a) Department notification. The operator shall contact the department or its agent for operational and testing guidance when notified of a suspected waterborne illness.
   2. (b) Suspected waterborne disease outbreak investigation. Pursuant to s. ATCP 72.09 (1) (a), as part of the investigation or inspection, the department or its agent may secure water samples for analysis.

   3. (c) Confirmed waterborne disease outbreak. A lodging facility that has a waterborne disease outbreak, as confirmed through laboratory analysis, shall complete all of the following:

      1. 1. Prevent continued exposure by implementing any of the following methods:

         1. a. Immediately discontinue public access to affected fixtures, equipment, and areas. _P
         2. b. Install point of use water treatment filters, where applicable. _P
         3. c. Other safeguards approved by the department. _P
         4. d. A combination of subd. 1. a., b., or c. _P

      2. 2. Develop a written remediation plan that includes all of the following _P:

         1. a. Identify the source of the waterborne pathogen. _Pf
         2. b. Identify the locations affected by the waterborne pathogen. _Pf
         3. c. The method that will be used to remove the pathogen from locations identified in subd. 2. a. and b. _Pf
      3. 3. Execute the remediation plan. _P
      4. 4. Collect post-remediation samples at least 48 hours after the execution of the remediation plan for locations identified under subd. 2. a. and b. _P
      5. 5. Obtain approval from the department or its agent to resume normal operations in affected areas. _P

      6. 6. If the confirmed waterborne disease outbreak is associated with Legionella spp., the operator, in addition to the requirements in this paragraph, shall complete all of the following:

         1. a. Notify incoming guests and staff about possible exposure to Legionella and symptoms of legionellosis until the operator has received approval from the department or its agent to resume normal operations. _Pf
         2. b. Notify guests from the previous 14 calendar days of the confirmed waterborne disease outbreak in writing as approved by the department about possible exposure to Legionella and symptoms of legionellosis. _Pf

         3. c. Develop and implement a water management program as approved by the department. _P

            Note: Resources for developing a water management plan include ANSI/ASHRAE standard 188 Legionellosis: Risk Management for Building Water Systems or the United States centers for disease control and prevention toolkit: Developing a Legionella Water Management Program.

         4. d. Arrange for sampling validation to be conducted at an Environmental Legionella Isolation Techniques Evaluation certified laboratory in accordance with the frequency established for sampling under subd. 6. c. _Pf

            Note: Laboratories can test their Legionella isolation techniques against standardized samples through the Environmental Legionella Isolation Techniques Evaluation Program. Participating labs receive a panel of lyophilized test samples twice each year from the Wisconsin State Laboratory of Hygiene. Some of the test samples are Legionella positive and some are Legionella negative. The test samples may also include other organisms commonly found in water. Participating labs process the test samples and report their results. Those labs that correctly identify Legionella in 2 consecutive panels receive documentation for passing the proficiency test.

4. (4) Plumbing.

   1. (a) General. A lodging facility shall meet Wisconsin building code pursuant to chs. 101 and 145, Stats., and chs. SPS 301 to 391, as applicable, as enforced by the Wisconsin department of safety and professional services.

   2. (b) Backflow prevention. A backflow or backsiphonage prevention device shall be installed on plumbing fixtures where the potential for contamination of the potable water supply exists. _P

      Note: Examples include mop sinks and chemical dispensing devices.

   3. (c) Air gap. When an air gap is required one of the following methods shall be used:

      1. 1. For waste piping one inch or less in diameter, the distance of the air gap shall be at least twice the diameter of the waste piping. _P

      2. 2. For waste piping larger than one inch in diameter, the distance of the air gap shall not be less than 2 inches. _P

         Note: An example includes a hotel ice dispenser where the required air gap is between the ice making water drain line or ice bin drain line and the floor drain.

History

History: CR 24-096: cr. Register October 2025 No. 838, eff. 1-25-26; correction in (2) (a) 2., (e) 2., 3., (g) 2. c., (i) (intro.), (3) (c) 1. d., 2. c., 6. (intro.), d. made under s. 35.17, Stats., and correction in (4) (a) made under s. 13.92 (4) (b) 7., Stats., Register October 2025 No. 838.