NR 812.35(1)(b)(b) 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.

NR 812.35(2)(2) 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 NoteNote: 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 NoteNote: As the result of an incorrect transcription of the amendment of sub. (2) by CR 13-099, that provision incorrectly read “Yard hydrants having hose threaded outlets...” from 10-1-14 to 11-1-16.

NR 812.35 HistoryHistory: 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.

NR 812.36(1)(1) 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.

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.

NR 812.36(2)(a)4.4. ‘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.

NR 812.36(2)(b)2.2. ‘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.

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.

NR 812.36(2)(c)2.2. ‘Size.’ 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.

NR 812.36(2)(c)4.4. ‘Cover.’ 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.

NR 812.36(2)(c)5.5. ‘Exceptions.’ 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.

NR 812.36(2)(d)2.2. ‘Alcoves.’ 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.