SPS 382.40 Note
Note: Values not specified in the table may be calculated by interpolation.
Table 382.40–3e
Conversion of Water Supply Fixture Units to Gallons
Per Minute for Water Treatment Devicesa Serving
an Individual Dwelling
b
- See PDF for table 
SPS 382.40(7)
(7)
Sizing of water supply piping. The sizing of the water supply system shall be based on the empirical method and limitations outlined in this subsection, an approved alternate standard per s.
SPS 381.20 (2), or an analysis provided by a Wisconsin registered architect, registered professional engineer or permitted designer of engineering systems – plumbing.
SPS 382.40 Note
Note: See appendix for details for alternative methods for sizing of the water supply piping of one- and 2-family and apartment buildings.
SPS 382.40(7)(a)
(a) Methodology. The determination of minimum pipe sizes shall take into account the pressure losses which occur throughout the entire water supply system and the flow velocities within the water distribution system. Calculations for sizing a water distribution system shall include:
SPS 382.40(7)(a)1.
1. The load factor in water supply fixture units or gallons per minute on the piping;
SPS 382.40(7)(a)2.
2. The minimum pressure available from the water main or pressure tank;
SPS 382.40(7)(a)4.
4. The pressure losses due to flow through water heaters, water treatment devices, water meters and backflow preventers;
SPS 382.40(7)(a)5.
5. The minimum flow pressure needed at the controlling plumbing fixture; and
SPS 382.40(7)(a)6.
6. The pressure losses due to flow friction through piping, fittings, valves and other plumbing appurtenances. This pressure loss may be calculated in terms of equivalent lengths of piping. The equivalent length of piping to a controlling plumbing fixture, including fittings, valves and other appurtenances, may be obtained by multiplying the developed length by 1.5.
SPS 382.40 Note
Note: See ch.
SPS 382 Appendix for further explanatory material.
SPS 382.40(7)(b)
(b) Private water mains and water services. Private water mains and water services shall be designed to supply water to the water distribution systems to maintain the minimum flow pressures specified in par.
(d), but shall not be less than 3/4
" in diameter.
SPS 382.40 Note
Note: See ch.
SPS 382 Appendix for further explanatory material.
SPS 382.40(7)(c)
(c) Maximum loading. The calculated load on any portion of the water distribution system may not exceed the limits specified in Tables 382.40-4 to 382.40-9.
SPS 382.40(7)(d)1.1. Except as provided in subd.
1. a. to
c., water supply systems shall be designed to provide at least 8 psig of flow pressure at the outlets of all fixture supplies.
SPS 382.40(7)(d)1.a.
a. The flow pressure at the outlets of the fixture supplies serving siphonic type urinals, washdown type urinals and washdown type water closets, siphonic type flushometer water closets and campsite water supply hose connections shall be at least 15 psig.
SPS 382.40(7)(d)1.b.
b. The flow pressure at the outlets of the fixture supplies serving one piece tank type water closets, pressure balance mixing valves, manufactured homes, and thermostatic mixing valves shall be at least 20 psig.
SPS 382.40(7)(d)1.c.
c. The flow pressure at the outlets of the fixture supplies serving blowout type urinals and blowout type water closets shall be at least 25 psig.
SPS 382.40(7)(d)1.d.
d. The flow pressure at the outlets of the fixture supplies serving any other fixture shall be the minimum pressure required by the manufacturer for the fixture, appliance, or equipment to operate.
SPS 382.40(7)(d)2.a.a. Except as provided in subd.
3., if the water pressure available from a water main or private water supply exceeds 80 psig, a pressure reducing valve and strainer, if a strainer is not a component of the valve, shall be installed in the water distribution system.
SPS 382.40(7)(d)2.b.
b. A pressure reducing valve required under subd.
2. a. shall be installed upstream from all plumbing fixtures and plumbing appliances and downstream from the water meter of an utility, if a meter is provided.
SPS 382.40(7)(d)3.
3. A pressure reducing valve shall not be required to be installed in a water distribution system which supplies water directly to a water pressure booster pump.
SPS 382.40(7)(d)4.
4. If the pressure or water supply volume available from the water main or private water supply is inadequate by calculation to provide the minimum pressures specified in subd.
1., a hydropneumatic pressure booster system or a water pressure booster pump shall be installed to increase the supply of water.
SPS 382.40(7)(d)4.a.
a. Each water pressure booster pump shall be provided with an automatic low pressure cut-off switch. The cut-off switch shall be located on the inlet side of the pump and shall be set to terminate the energy supplied to the pump when a positive pressure of less than 10 psig occurs. Pressure gauges shall be installed on the influent and effluent piping.
SPS 382.40(7)(d)4.b.
b. A vacuum relief valve not less than one-half inch in diameter shall be installed in each water pressure tank, if the bottom of the pressure tank is more than 20 feet above any water supply outlet served by the pressure tank.
SPS 382.40(7)(e)
(e) Maximum velocity. A water distribution system shall be designed so that the flow velocity does not exceed 8 feet per second except for combination sprinkler distribution piping as designed in sub.
(3) (e).
SPS 382.40(7)(f)1.1. Water distribution piping 1/2" in diameter serving 2 or more plumbing fixtures may not have a load of more than 2 water supply fixture units.
SPS 382.40(7)(f)2.
2. Water distribution piping 1/2" in diameter serving a shower which is not individually pressure balanced or individually thermostatically blended may not serve any additional fixtures.
SPS 382.40(7)(g)
(g) Minimum sizes for fixture supplies. Except as provided in subds.
1. to
3., the fixture supplies serving all plumbing fixtures, appliances and pieces of equipment shall be at least 1/2" in diameter.
SPS 382.40(7)(g)1.
1. Fixture supplies serving syphon jet type urinals shall be at least 3/4" in diameter.
SPS 382.40(7)(g)2.
2. Fixture supplies serving flushometer type water closets shall be at least one inch in diameter.
SPS 382.40(7)(g)3.
3. Fixture supplies serving emergency eye wash or shower outlets shall be not less than recommended by the manufacturer.
SPS 382.40(7)(g)4.
4. Water distribution piping less than 1/2 inch diameter shall have a minimum 1/4 inch diameter, serve one plumbing fixture, the served fixture shall have a maximum load factor of .5 water supply fixture units, and the developed length shall be 25 feet or less.
SPS 382.40(7)(h)1.a.a. Except as provided in subd.
1. b. and
c., fixture supply connectors may not exceed more than 24" in developed length upstream from a plumbing fixture or the body of a faucet.
SPS 382.40(7)(h)1.b.
b. A fixture supply connector located downstream of a water cooler, water treatment device or water heater which individually serves a faucet or outlet may not exceed more than 10 feet in developed length.
SPS 382.40(7)(h)1.c.
c. A fixture supply connector located upstream of a water treatment device serving no more than 2 fixtures or outlets may not exceed 10 feet in developed length.
SPS 382.40(7)(h)2.
2. Fixture supply connectors may not extend more than 10 feet in developed length upstream of a plumbing appliance.
SPS 382.40(8)(a)1.1. Adequate measures shall be taken to protect all portions of the water supply system from freezing. All private water mains and water services shall be installed below the predicted depths of frost specified in s.
SPS 382.30 (11) (c) 2. d., Figure 382.30-1 and Table 382.30-6, unless other protective measures from freezing are taken.
SPS 382.40(8)(a)2.
2. A hose bibb or a hydrant that penetrates an exterior wall of a heated structure shall be a frost proof and self-draining type.
SPS 382.40 Note
Note: See s.
SPS 382.41 (4) (m) relative to cross connection control devices.
SPS 382.40(8)(b)1.1. Exterior water supply piping may not be located in, under or above sanitary sewer manholes, or POWTS treatment, holding or dispersal components.
SPS 382.40(8)(b)2.
2. If a private water main or a water service crosses a sanitary sewer, the water piping within 5 feet of the point of crossing shall be installed in accordance with any of the following requirements:
SPS 382.40(8)(b)2.a.
a. The water piping shall be installed at least 12 inches above the top of the sewer.
SPS 382.40(8)(b)2.b.
b. The water piping shall be installed at least 18 inches below the bottom of the sewer.
SPS 382.40(8)(b)2.c.
c. The water or sewer piping shall be installed within a waterproof sleeve made of materials as specified for sanitary building sewers in s.
SPS 384.30 (2).
SPS 382.40(8)(b)3.
3. Except as permitted in subds. 4 and
5., private water mains and water services shall be installed at least 5 feet horizontally from any sanitary sewer.
SPS 382.40 Note
Note: The Department of Natural Resources has limitations for the separation of water mains and sanitary sewers.
SPS 382.40(8)(b)4.
4. Private water mains and water services may be installed less than 5 feet horizontally from a pressurized sanitary sewer if all of the following conditions are met:
SPS 382.40(8)(b)4.a.
a. The bottom of the water piping is installed at least 18 inches above the pressurized sewer.
SPS 382.40(8)(b)4.b.
b. The water piping is installed at least 3 feet horizontally from the pressurized sewer.
SPS 382.40(8)(b)5.
5. Private water mains and water services may be installed less than 5 feet horizontally from a non-pressurized sanitary sewer if any of the following conditions are met:
SPS 382.40(8)(b)5.a.
a. The bottom of the water piping is installed at least 12 inches above the sewer.
SPS 382.40(8)(b)5.c.
c. The water service is 2 inches or less in diameter and is located more than 24 inches from the sewer.
SPS 382.40(8)(b)6.
6. The portion of a private water main or water service within 5 feet of developed length from the point where the water service first enters the building may be less than 12 inches above the sewer and within 24 inches of the sewer.
SPS 382.40(8)(b)7.
7. No private water main or water service may be installed within 6 inches of a storm sewer.
SPS 382.40 Note
Note: See ch.
SPS 382 Appendix A-382.30 (11) (d) for setback distance from yard hydrant to well.
SPS 382.40 Note
Note: See ch.
SPS 383 Table 383.43–1 for setback distances to POWTS components.
SPS 382.40(8)(b)9.
9. No underground water supply storage tank shall be installed within 8 feet of a storage vessel containing a substance of a higher hazard than that contained in the water supply storage tank.
SPS 382.40(8)(b)10.
10. Private water mains shall be provided with provisions for flushing of the system at a minimum of 10 feet per second until clear.
SPS 382.40 Note
Note: See ch.
SPS 382 appendix for further explanatory information.
SPS 382.40(8)(c)
(c) Limitations. No private water main or water service may pass through or under a building to serve another building unless one of the following conditions are met:
SPS 382.40(8)(c)1.
1. The private water main or water service serves farm buildings or farm houses, or both that are all located on one property.
SPS 382.40(8)(c)2.
2. The private water main or water service serves buildings that are located on the same property and a document which indicates that the piping and distribution arrangement for the property and buildings will be recorded with the register of deeds no later than 90 days after installation.
SPS 382.40(8)(d)2.
2. Provisions shall be made to evacuate all water out of the water distribution system.
SPS 382.40(8)(d)3.a.a. Except where parallel water meters are installed, water distribution piping shall be provided to bypass a water meter 1
½
‶ or larger.
SPS 382.40(8)(d)3.b.
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.
SPS 382.40(8)(d)4.
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.
SPS 382.40(8)(d)5.
5. A bypass shall not be required when a water treatment device serves no more than 2 fixtures or outlets.
SPS 382.40(8)(d)6.
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).
SPS 382.40(8)(d)7.
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.
SPS 382.40(8)(d)8.
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.
SPS 382.40 Note
Note: For information on sample valve requirements see s.
NR 812.34 (2).
SPS 382.40(8)(d)9.
9. A water treatment device that consists of 2 or more treatment tanks shall also have a hygienic sampling valve between each treatment tank.
