Tanks relying on expansion of a flexible membrane within a restricting container, rather than on a water to air interface to provide pressure in the water system, may be used. All pressure tanks for storing potable water under pressure, including those having an air space for expansion, shall be identified by seal, label or plate indicating the manufacturers name and model number and shall meet the following specifications:
Pressure tanks to be buried shall be constructed of steel, fiberglass or other comparable non-metallic composite material. Steel tanks with metallic discharge piping, meeting the requirements of s. NR 812.28
, shall be used in contaminated soil areas. Steel tanks to be buried shall have a minimum wall thickness of 0.25 inches. Fiberglass or other non-metallic tanks to be buried shall have the structural strength to prevent collapse of the tank. Manufacturer's instructions shall be followed. All buried tanks shall be back-filled in place with sand, compacted in place. Steel pitless receiver tanks, when they are part of approved pitless units attached directly to the well casing pipe, shall also have a minimum wall thickness of 0.25 inches. Any air unloader pipe, tank air valve or any other pipe connection extending up to the ground surface shall be steel pipe meeting the requirements of s. NR 812.28
and shall terminate at least 12 inches above ground grade.
NR 812.33 Note
The department recommends that a surface air check kit be installed for a buried pressure tank to check, maintain and adjust the air pressure pre-charge of the tank. Also, in uncontaminated soil areas, pipe and pipe connections to the tank should be made with flexible pipe and fittings meeting the requirements of s. NR 812.28
to minimize strain or pressure on the tank or the tank fittings.
Pressure tanks having a gross volume in excess of 500 gallons, and not having a water to air interface bladder, shall have the following:
If the tank is buried, all electrical controls extended to at least above ground grade.
Each tank shall have an access manhole, a drain, and pressure gauge, pressure relief valve, water sight glass and pressure or probe operated controls for the pumps.
Any interior protective materials including but not limited to liners, paints, coatings,or sealants shall be certified for potable water use under NSF Standard 61.
NR 812.33 Note
Note: The department recommends that the tank have bypass piping to allow operation of the system while the tank is being repaired or painted.
(b) Pressure tanks larger than 1,000 gallons gross volume.
An approval shall be obtained for pressure tanks having a gross volume greater than 1,000 gallons. The department recommends that pressure tanks having a volume greater than 1,000 gallons be installed above ground. When approved, the tank shall be installed according to the requirements of par. (a)
. When tanks of this size are approved for burial, the head end of the tank shall be cradled in a basement wall or in the wall of an approved pit to provide access and shall be constructed to the specifications for pits described in s. NR 812.36 (2)
to provide access to the head of the tank. The pit shall have other additional support cradles. Pitless receiver tanks having a volume greater than 1,000 gallons may be installed without an access pit.
(2) Nonpressure storage vessels.
Nonpressure storage vessels, designed as part of a potable water supply system, may not be installed without approval from the department under s. NR 812.09
. Approval is required regardless of whether or not there is a free-air gap in the water inlet line upstream of the vessel. Vessel approval is based on methods of construction and sanitary provisions. The installation of a surge tank is exempt from this approval requirement.
(b) Reservoirs and elevated storage tanks.
A reservoir may be constructed to store water if it is constructed above the groundwater level and in accordance with this paragraph and Figure 7 of ch. NR 812 Appendix
Gravity supply pipes shall be located entirely above grade and shall be conducted to the reservoir through the roof or through the curbing for the manhole. The overflow pipe described in subd. 1. b.
may be installed at such a level to provide a free-air gap. Buried supply pipe shall be maintained under a continuous pressure head which is greater than the ground surface elevation.
NR 812.33 Note
Note: The department recommends that trees and shrubs not be planted within 25 feet of a reservoir.
An exposed overflow pipe shall be located just under the roof of the reservoir or outside the elevated storage tank and shall extend at least 8 feet away. The overflow pipe shall terminate with a downturned, screened elbow located at least 12 inches above ground grade. The pipe shall discharge onto a splash plate and have sufficient diameter to permit wasting water at a rate in excess of the inflow from the water source.
2. `Steel construction specifications.'
Steel reservoirs or elevated storage tanks shall meet the requirements of AWWA D100-84 for welded construction or AWWA D103-80 for bolted construction.
Water storage structures shall be designed with convenient access for cleaning and maintenance.
4. `Concrete construction specifications.'
Reservoirs constructed of concrete shall meet the following specifications:
An impervious flexible water stop strip for wall construction joint and a reservoir drain facility shall be installed before the concrete is poured.
The floor of the reservoir shall be reinforced poured concrete with a thickness of at least 6 inches and shall have a curbing wall 6 inches high and 6 inches thick having a keyway or a flexible water stop strip for a construction joint with the walls.
The walls of the reservoir shall be reinforced poured concrete at least 6 inches thick and terminate above the established ground grade.
The roof shall be reinforced poured concrete at least 6 inches thick and shall extend at least 12 inches above established ground grade. An access manhole at least 20 inches in diameter or 20 inches square shall be constructed as an integral part of the roof. The manhole shall have a curbing wall extending at least 12 inches above the roof. The department recommends that the manhole shall be constructed entirely of 4-inch thick reinforced poured concrete, but may be fabricated of 1/4-inch steel or cast iron frame with a gasket and bolted cover. The curbing shall be provided with a snug fitting, overlapping cover with a minimum of 3-inch wide skirted sides. The department recommends that the cover be constructed with welded sheet steel, but may be constructed with reinforced poured concrete. Concrete shall be mixed according to the requirements specified in s. NR 812.11 (15) (e)
`Location requirements.' A reservoir shall be located according to the requirements of s. NR 812.08
, including the minimum separation distance requirements of s. NR 812.08 (4)
established for existing or proposed potential sources of contamination.
(3) Painting and cathodic protection.
Metal surfaces of reservoirs or elevated storage tanks, to be in contact with potable water, shall be protected by paints, other protective coatings, or by cathodic protection except when documentation is provided to the department that the source water will not be aggressive or corrosive to the metal surfaces. Paint or coating systems shall conform with AWWA standard D102 and shall be NSF approved for use with potable water. When cathodic protection is to be provided, it shall be designed and installed by competent technical personnel. A copy of the AWWA standards are available for inspection at the office of the department of natural resources, the secretary of state's office and the office of the revisor of statutes, and may be obtained for personal use from AWWA, Inc., 6666 W. Quincy Avenue, Denver, Colorado 80235.
NR 812.33 History
Cr. Register, January, 1991, No. 421
, eff. 2-1-91; am. (1) (a) (title), 1., (b), (2) (b) 1. a., Register, September, 1994, No. 465
, eff. 10-1-94; am. (1) (a) (intro.), 1., Register, September, 1996, No. 489
, eff. 10-1-96; correction in (3) under s. 13.92 (4) (b) 6.
, Stats., Register July 2010 No. 655
; CR 13-099
: am. (1) (a) 1., cr. (1) (a) 2. d., am. (1) (b), (2) (intro.), cr. (2) (b) 5., am. (3), r. and recr. Figures 36b., 36c. Register September 2014 No. 705
, eff. 10-1-14; CR 18-095: am. (1) (b), (2) (intro.), (b) (intro.), 4. e. Register June 2020 No. 774, eff. 7-1-20; (2) (b) 5. (title) created under s. 13.92 (4) (b) 2., Stats., Register June 2020 No. 774.
A pump installer shall install a sample faucet in accordance with all of the following requirements:
The sample faucet shall be installed at or upstream of the pressure tank and upstream of any water treatment equipment for collection of water samples directly from the well.
The sample faucet shall be installed at least 12 inches above the floor, have a downturned spout, and be in an accessible location. All sample faucets shall be metal and shall have an inside diameter of at least 1/4 inch. The sample faucet shall have a smooth end. Threaded faucets and threaded drain valves may not be installed in place of a smooth end sample faucet even if the threads have been filed off. Petcocks may not be used as sample faucets. Any faucet used for recirculation shall be installed with a hose connection vacuum breaker.
Sample faucets shall be installed in the pump discharge piping upstream of the pressure tank entry except in any of the following cases:
When a buried pressure tank, a pitless receiver tank or an above ground discharge unit is installed, the sampling faucet shall be installed immediately following the point of entry into the building or building basement.
When an approved above ground discharge unit is used and the pressure tank is in the basement, the sampling faucet shall be installed in the service pipe from the tank at least 12 inches above the floor. The sampling faucet may be placed in the pump discharge line if there is no loss of air from the system when the faucet is opened.
An entry point sample faucet shall also be installed for a non-community water system after treatment or chemical addition, if any, but prior to the distribution system for sample collection and compliance with the monitoring requirements of ch. NR 809
. The entry point sample faucet shall meet all the requirements specified in sub. (1) (b)
NR 812.34 History
Cr. Register, January, 1991, No. 421
, eff. 2-1-91; am. (intro.), (1), Register, September, 1994, No. 465
, eff. 10-1-94; CR 13-099
: am. (title), (intro.) Register September 2014 No. 705
, eff. 10-1-14; CR 18-095: r. and recr. Register June 2020 No. 774, eff. 7-1-20; correction in (1) (c) 2. made under s. 35.17, Stats., Register June 2020 No. 774.
NR 812.35 Yard hydrants.
Yard hydrants may be installed in a water system provided they are not installed in or on a well and have been approved by the department of safety and professional services for this purpose. All backflow prevention devices shall comply with ch. SPS 384
and shall be installed and maintained in accordance with ch. SPS 382
Yard hydrants having hose threaded outlets shall either:
Have a hose connection vacuum breaker installed on the hose threads.
Have a reduced pressure principle backflow preventer or a backflow preventer with intermediate atmospheric vent installed in the water supply pipe which serves only the yard hydrant or hydrants.
Yard hydrants without hose threaded outlets may be installed without additional backflow protection if the outlet of the yard hydrants complies with the air gap requirements in s. SPS 382.41
NR 812.35 Note
Chapter SPS 384
requires that backflow prevention devices such as hose connection vacuum breakers, backflow preventers with intermediate atmospheric vent and reduced pressure principle backflow preventers must be reviewed by and receive device approval from department of safety and professional services. Chapter SPS 382
requirements do not allow backflow preventers to be buried or installed in a pit. Installation of hose connection vacuum breakers in areas subject to freezing must be of the type that allows draining. Department of safety and professional services plan approval must be received prior to the installation of a reduced pressure principle backflow preventer. Reduced pressure principle backflow preventers must be installed by a plumber licensed under ch. 145
, Stats. and listed by department of safety and professional services to do such work. The device must be tested at least once a year by a department of safety and professional services listed backflow prevention device tester.
NR 812.35 Note
As the result of an incorrect transcription of the amendment of sub. (2) by CR 13-099
, that provision incorrectly read “Yard hydrants
hose threaded outlets...” from 10-1-14 to 11-1-16.
NR 812.35 History
Cr. Register, January, 1991, No. 421
, eff. 2-1-91; correction in (intro.) made under s. 13.93 (2m) (b) 12., Stats., Register, September, No. 465
; corrections made under s. 13.93 (2m) (b) 4., Stats., Register, September, 1996, No. 489
; correction in (intro.) made under s. 13.93 (2m) (b) 7., Stats, Register, May, 2000, No. 533
; correction in (intro.), (3) made under s. 13.92 (4) (b) 7., Stats., Register December 2011 No. 672
; CR 13-099
: am. (intro.), r. (1), renum. (2), (3) to (1), (2) and am. Register September 2014 No. 705
, eff. 10-1-14; CR 13-099
transcription error in (2) corrected Register Otober 2016 No. 730; correction in (1) (a) made under s. 35.17, Stats., Register June 2020 No. 774.
Approvals to construct pits.
A pit structure that is completely or partially below the ground surface or below a building floor used for the housing of wells, off-set pumps, pressure tanks, or heads of pressure tanks may not be constructed without prior written approval from the department under s. NR 812.09
. Pits used only for the housing of valves are exempt from the requirements of this section except that a pit used for this purpose shall be watertight, may not be connected to a sewer, shall be drained to permeable soil or to the ground surface and may not be subject to flooding.
(2) Specification for new pits.
Pits shall conform to Fgure 8 of ch. NR 812 Appendix
and all of the following minimum specifications:
NR 812.36(2)(a)1.1. `Area.'
Five square feet of free floor area shall be provided for each square foot of area required for any pump installation equipment. The inside area of a pit may not be less than 24 square feet.
The width of the pit shall be not less than 2/3 of the length.
`Height.' The height inside shall be at least 6 feet, but not less than 6 inches higher than any equipment installed in the pit.
`Walls, floor and roof thicknesses.' The wall thickness shall be at least 6 inches and waterproof. The floor thickness shall be at least 4 inches when the floor bears on a footing. Floors used as a wall footing shall be at least 6 inches thick from the outside edge of the floor to a point at least one foot inside the wall of the pit. The roof thickness shall be at least 5 inches.
NR 812.36(2)(b)1.1. `Material.' The pit shall be constructed of reinforced poured concrete thoroughly puddled in place. The concrete shall be prepared to meet the requirements specified in s. NR 812.11 (15) (e) or by using clear water and washed sand and gravel or crushed rock in the following proportions: 1 part cement, 2 parts sand, and 3 parts gravel. The water-cement ratio may not exceed 6 gallons of water per 94 pounds of cement. A 6-bag concrete mix per cubic yard with a 28-day design strength of at least 3,000 lbs. per foot and a slump test of no more than 3 inches may be used.
`Watertight juncture.' The junction of walls, floor and roof shall be made watertight by use of water stops or keyed joints. Conduits or similar connection with the pit shall be watertight.
The deck or pit roof and walls of the pit structure shall be reinforced with bars or wire mesh to insure strength and durability.
4. `Elevation of pit roof.'
The pit roof, deck or wall top shall be above the ground surface.
NR 812.36(2)(c)1.1. `Placement.'
The pit shall be provided with a manhole opening. The opening shall be located directly over the well, unless the well casing pipe itself extends through the roof, or if a capped section of well casing pipe at least equal in diameter to the well casing pipe is cast into the pit roof directly over the well.
The manhole opening shall be at least 20 inches square or 20 inches in diameter and shall be sufficiently large to allow entrance or removal of any unit or equipment to be installed in the pit.
The manhole opening shall be provided with a raised concrete curbing at least 4 inches thick. The curbing shall extend at least 4 inches above the pit roof.
A structurally substantial, watertight, overlapping, tight-fitting, cover with skirted sides at least 3 inches high shall be provided for the manhole. The department recommends that a welded sheet steel cover be used, but a cover made out of lumber and covered in turn with sheet metal or tin may be acceptable if waterproof.
A watertight, cast iron manhole frame and cover with a gasket may be substituted for a curbed manhole. When the pit is an alcove adjoining a basement foundation, a watertight concrete plug may be substituted for a curbed manhole if the roof of the pit terminates in a walkway, breezeway, patio or porch, providing the pit is reasonably accessible.
NR 812.36(2)(d)1.1. `Gravity drain.'
The pit shall be drained by a watertight gravity drain discharging to the ground surface at a point at least 8 feet from the well. The drain shall be constructed of materials conforming to ch. SPS 384
and shall have a minimum diameter of 2 inches with a screened outlet.
An alcove may be drained to the basement floor if the pit floor slopes toward the basement and if the basement is adequately drained. If the basement is not adequately drained, a gravity drain shall be provided for the pit. The pit floor shall be one foot above the basement floor.
(e) Termination of well casing pipe.
The well casing pipe shall terminate at least 12 inches above the pit floor and be provided with an approved watertight seal.
NR 812.36(2)(f)1.1. `Pit.'
A pit should be vented with 2, 2-inch diameter or larger galvanized steel pipes located in opposite corners, one pipe to extend to within one foot of the pit floor and the other to extend only through the pit roof. If used, the upper end of the vent pipes shall terminate with return bends and screened outlets.
The well vent pipe shall extend to the top of the pit and terminate with a return bend and a screened outlet.
(g) Pump installation.
The free space in the pit around the well casing pipe shall be maintained so that the top of the well casing pipe is readily accessible for installation, adjustment or removal of an approved well seal and for the installation and removal of the pump or piping.
(3) Driveway ramps.
If a well must be located in a driveway, parking area, walkway or other high traffic area due to small lot size, accessibility constraints or inability to otherwise meet the minimum separation distance requirements of s. NR 812.08
, the well may be contained within a driveway ramp structure without department approval provided the driveway ramp meets the specifications of this subsection.
Relation to floodplain.
Driveway ramps may not be constructed in a floodway or floodplain.
Driveway ramps shall conform to Figure 9 of ch. NR 812 Appendix
and all of the following minimum specifications:
1. `Nonpressurized conduit.'
If the well has a nonpressurized conduit, the pump installer shall evaluate the integrity of the nonpressurized conduit and its connection to the well casing pipe by performing a pressure test. If the nonpressurized conduit fails the pressure test, the nonpressurized conduit shall be eliminated and the installation shall be changed to a pitless connection in accordance with s. NR 812.42 (11) (e)
. Wells with nonpressurized conduits must be vented to the ceiling in the basement and shall have the pump cables enter through a conduit.
The top of the well shall be contained within a manhole and frame that is set on a concrete ring. The manhole shall be water-tight with a gasketed seal and shall be bolted securely to the frame. The manhole must be surrounded by concrete or asphalt that is sloped so that surface water does not flow toward or pond on the manhole cover.
3. `Height of well.'
The top of the well casing pipe shall terminate a minimum of four inches above the original grade of the driveway, parking lot or sidewalk.
4. `Well seal.'
The top of the well shall be sealed watertight with an approved sanitary well seal.
5. `Conduit for electrical cable.'
Conduit for electrical wiring shall be protected and sealed to comply with s. NR 812.30 (5)
. If the conduit extends from the well seal to a basement, the end of the conduit shall be sealed with a watertight, vermin-proof seal.
NR 812.36 History
Cr. Register, January, 1991, No. 421
, eff. 2-1-91; am. (1), Register, September, 1994, No. 465
, eff. 10-1-94; correction in (2) (d) 1. made under s. 13.93 (2m) (b) 7., Stats., Register, May, 2000, No. 533
; correction in (2) (d) 1. made under s. 13.92 (4) (b) 7., Stats., Register December 2011 No. 672
; CR 13-099
: cr. (3), Figures 45A, 45B Register September 2014 No. 705
, eff. 10-1-14; CR 18-095: am. (1), (2) (intro.), (b) 1., (c) 5., (d) 2., (3) (b) (intro.), 1., 5., r. (3) (b) 6. Register June 2020 No. 774, eff. 7-1-20.
This section applies to treatment of water for potable use in a private or non-community water system except for the disinfection, batch chlorination, and acidification prescribed in ss. NR 812.12
, and 812.41
Water treatment devices installed in a water system shall have a plumbing product approval in accordance with chs. SPS 382
A water supply requiring approval under sub. (3)
shall produce water free from coliform bacteria prior to treatment, unless the department determines that a water supply free from coliform bacteria is not available.
Water treatment devices shall be installed in accordance with the manufacturer's printed instructions, chs. SPS 382
, and, if specified, department written installation approval conditions. If there is a conflict between the manufacturer's instructions and the code requirements or approval conditions, the code requirements and approval conditions shall take precedence.
A water treatment device shall be installed by one of the following: