Wisconsin Legislature: SPS 382.40(8)(i)2.a.

a. Except where parallel water meters are installed, water distribution piping shall be provided to bypass a water meter 1½″ or larger.

b. The minimum diameter of water distribution piping serving as a meter bypass shall be one nominal pipe size smaller than the meter. Water distribution piping serving as a meter bypass shall be of the same material and shall be equal to or one nominal pipe size smaller than the water distribution piping immediately downstream of the meter.

4. Except as provided in subds. 5. and 6., a bypass shall be provided to serve a water treatment device. The bypass piping may be an internal part of the water treatment device.

5. A bypass shall not be required when a water treatment device serves no more than 2 fixtures or outlets.

6. A bypass shall be prohibited for a water treatment device installed to reduce a contaminant in order to comply with the provisions in s. SPS 382.70 (3).

7. When water distribution piping larger than the code minimum is used the system shall be designed to allow effective flushing of the system at 8 feet per second.

8. Hygienic sampling valves shall be installed within 6 feet, upstream and downstream, of a chemical injection system or water treatment device installed to mitigate a contaminant regulated under ch. NR 809 or NR 140.

Note: For information on sample valve requirements see s. NR 812.34 (2).

9. A water treatment device that consists of 2 or more treatment tanks shall also have a hygienic sampling valve between each treatment tank.

10. Any portion of the water distribution system terminating by means of a plug, cap, or closed fitting and dry downstream with no outlet may not exceed 6 pipe diameters.

(e) Valves.

1. All control valves installed in a water service, except a valve serving only as a corporation cock, shall be accessible.

2. Stop- and waste-type control valves may not be installed underground except in the following situations:

a. Fire hydrants intended for fire fighting.

b. Two-inch and larger diameter hydrants serving municipal wastewater treatment plants.

c. Emergency fixtures.

3. All control valves and fixture stop valves installed in a water distribution system shall be accessible. Control valves for the individual plumbing fixtures and appliances within dwelling units shall be accessible from within the dwelling unit.

Note: The installation of two water services or a private water main may require the installation of a check valve. Refer to ch. NR 811 for more information.

(f) Water hammer arrestors. All plumbing fixtures, appliances and appurtenances with 3/8” or larger inlet openings and with solenoid actuated quick closing valves shall be provided with water hammer arrestors. Water hammer arrestors shall be installed in the fixture supplies serving the fixtures, appliances or appurtenances. Water hammer arrestors shall be accessible.

(g) Temperature control. The water temperature to all showers in public buildings shall be controlled by thermostatic or combination thermostatic-pressure balanced mixing valves or by individually controlled pressure balanced mixing valves. A thermostatic or combination thermostatic-pressure balanced mixing valve may not be bypassed.

(h) Fittings and connections. The drilling and tapping of water supply piping shall be prohibited except for:

1. Corporation cocks for a water service or a private water main; and

2. Self-tapping valves which serve individual plumbing appliances.

(i) Flushing and disinfection of potable water supply systems.

a. Before a newly constructed water supply system is to be put into use, the piping of the system shall be flushed with water and disinfected. Each water outlet shall be flushed beginning with the outlet closest to the building control valve and then each successive outlet in the system. The flushing at each water outlet shall continue for at least 1 minute and until the water appears clear and with no trace of disinfectant at the outlet.

b. Each portion of a water supply system which is altered or repaired shall be flushed for at least one minute and until the water appears clear.

2. New private water mains and extensions to private water mains shall be disinfected prior to use in accordance with AWWA C651 or the following method:

a. The pipe system shall be flushed with clean water until no dirty water appears at the points of outlet.

b. The system or part thereof shall be filled with a solution of water and chlorine containing at least 50 parts per million of chlorine and the system or part thereof shall be valved off and allowed to stand for 24 hours or the system or part thereof shall be filled with a solution of water and chlorine containing at least 200 parts per million of chlorine and allowed to stand for 3 hours.

c. Following the allowed standing time, the system shall be flushed with clean potable water.

d. The procedures shall be repeated if it is shown by a bacteriological examination that contamination still exists in the system.

3. The department may require a water quality analysis to be done for a new or repaired water supply system. The analysis shall be performed in accordance with acceptable nationally recognized laboratory practices. If the water supply system has been disinfected, water samples for the analysis may not be taken sooner than 24 hours after disinfection.

Note: See s. SPS 384.30 (1) regarding the bending of pipe and protection from puncture.

4. New or repaired combination water services or combination private water mains shall be flushed and disinfected prior to use in accordance with NFPA 24.

(j) Water softeners. Ion exchange water softeners used primarily for water hardness reduction that, during regeneration, discharge a brine solution shall be of a demand initiated regeneration type equipped with a water meter or a sensor unless a wastewater treatment system downstream of the water softener specifically documents the reduction of chlorides.

(jm) Water tanks. Water tanks for public, potable use shall meet all of the following criteria:

1. ‘Pneumatic pressure tanks.’ Pneumatic pressure tanks shall conform to all of the following:

a. Tanks shall conform to ch. SPS 384.

b. Tanks shall be served by a pressure relief valve.

c. Tanks shall be able to be isolated for maintenance, repair, or replacement and equipped with a drain valve by means of a control valve.

d. Water calculations incorporating the size of a pneumatic pressure tank may use a 5-minute peak flow in gallons per minute for the water supply system. The system shall be designed to minimize stagnation.

e. Tanks shall be stamped or labeled showing the manufacturer’s name, model number, the tank volume, year manufactured, and the allowable working pressure.

2. ‘Storage tanks.’

a. Storage tanks shall conform to ch. SPS 384.

b. All water storage tanks and structures shall be watertight and exclude water, rain, snow, birds, animals, insects, and dust.

c. Exterior translucent tanks shall be shielded from direct sunlight.

3. ‘Separation.’ Potable water may not be stored in a tank or compartment adjacent to non-potable water when the two compartments are separated by a single wall.

4. ‘Locks.’ Locks shall be provided on access manholes, inspection covers, fill pipe, fences, ladder cage bottoms, and any other locations deemed necessary to prevent trespassing, vandalism, and sabotage.

5. ‘Drain piping.’ Piping used to drain a storage tank or structure shall discharge to the ground surface through an air gap. The drain may discharge over a drainage inlet receptor, splash pad, or rip rap.

6. ‘Overflow.’

a. Tanks or reservoirs shall be provided with overflow piping. The pipe shall open downward between 6 and 12 inches over a drainage inlet, splash pad, or rip rap. Interior tanks within the building structure shall provide overflow piping discharging to an approved clearwater receptor or as approved by the department.

b. The overflow outlet pipe shall be provided with a 4-mesh non-corrodible screen.

c. The overflow outlet pipe shall be of approved material in accordance with Table 384.30-8.

d. The overflow outlet pipe shall be sized to permit discharge flow in excess of the maximum fill rate of the inlet pipe flow.

e. Overflow piping shall be visible at the discharge location.

f. For storage tanks or reservoirs with more than one compartment and where each compartment can be isolated from the other compartments each compartment shall be provided with its own overflow pipe.

7. ‘Inlet and outlet piping.’

a. Inlet and outlet piping from a tank or storage structure shall be sized in accordance with s. SPS 382.40 (7).

b. Piping shall be of approved material in accordance with Table 384.30-8 for locations within the building, above floor, Table 384.30-7 for locations below grade and outside of the building foundation parameters.

8. ‘Access.’

a. Water tanks or structures shall have convenient access for cleaning and maintenance.

b. Manhole openings shall be fitted with a solid watertight cover which overlaps the framed opening and extends down around the opening frame a minimum of 2 inches. A watertight gasket shall be attached to the bottom side of the manhole cover.

c. Manhole covers for buried tanks or structures shall be no less than 24 inches above a sloped finished grade.

d. Inspection covers shall be watertight and locked securely to prevent unauthorized access.

e. Interior paints or coatings shall conform to NSF/ANSI Standard 61.

9. ‘Bypass piping.’ Bypass piping shall be provided allowing the tank or reservoir to be taken out of service for maintenance and inspection purposes when directly connected to a well or municipal water supply.

10. ‘Vents.’

a. Storage tanks shall be vented to the atmosphere. The overflow pipe may not be considered a vent.

b. Vents shall be constructed of water distribution materials as per Table 384.30-8, or as approved by the department.

c. Vents shall terminate above the top of the tank in a U-bend or vent cap with the opening 24 to 36 inches above grade and covered with a 24-mesh stainless steel screen at a location that is secured.

d. Minimum vent size shall allow an air flow consistent with water inflow and outflow rates and shall be not less than 2 inches.

11. ‘Location.’

a. Exterior tanks may not be located within a flood plain or floodway or within 2 feet above the regional flood elevation.

b. The area surrounding a storage tank shall be graded to prevent standing surface water within 50 feet of the tank.

c. Storage tanks shall be located in an area that is accessible year-round.

d. Tanks shall be separated from potential contamination sources by the applicable separation distances contained in chs. NR 811 and 812 or as otherwise approved by the department of natural resources or as approved by the department.

Note: See ch. SPS 382 Appendix for further explanatory material. Section NR 812.08 may require additional setbacks.

e. The top roof of an exterior tank may not be less than 2 feet above grade level.

12. ‘Controls.’

a. Atmospheric pressure tanks shall have a means for maintaining pressure within the building water distribution system. A hydro-pneumatic tank, pump facilities, or other reliable methods shall be provided to maintain system pressure.

b. Manual valves shall be installed in the water distribution system to isolate tank and pump equipment from the water distribution system.

c. Valves designated for operation of the storage tank shall be visibly recognized as being open or closed. Solenoid valves shall have a control system panel that will have indicators showing visual valve open or closed status.

d. Drain valves shall be provided to allow access to the storage tank for maintenance purposes.

e. A high water fill valve or float valve shall maintain the storage tank levels to the minimum water storage required for use. A bypass to the fill valve shall be provided.

f. Tank water levels shall be observable by means of a sight level indicator.

g. A pressure gauge shall be installed downstream of the storage tank and booster pumps.

h. A thermometer or sensor shall be installed on the storage tank for water temperature monitoring purposes.