NR 811.71(7)(7) Flushing hydrants. Flushing hydrants or blow-off installations shall be installed at all dead ends and at intermediate locations as necessary in order to remove sediment and optimize water quality for all water systems that do not provide fire protection. Flushing hydrants shall be sized to provide a minimum velocity of 3 feet per second in the water main being flushed. Flushing hydrants shall allow frost-proof operation. If necessary, flushing hydrants shall be pumped out prior to freezing weather.

NR 811.71(8)(8) Sampling hydrants and faucets. All water systems shall be provided with a sufficient number of sampling faucets, hydrants, or stations to provide representative water quality sampling sites throughout the water distribution system including extremities and dead ends. An adequate number of sampling sites shall be provided as required under the department’s monitoring plan requirements contained in ch. NR 809 to meet all of the department’s water quality sampling requirements. Sampling faucets, hydrants, and stations shall be protected from contamination and vandalism to the extent possible. Locks shall be provided for sampling station enclosures. Fire hydrants may not be considered as sampling hydrants. All sampling locations shall be pumped out prior to freezing weather if necessary. Sampling installations may not have drain-to-soil weep ports and shall not drain to any sanitary or storm sewer.

NR 811.72(1)(1) Air-relief facilities. If possible, water mains shall be constructed to avoid high points at which air can accumulate. Permanent provisions shall be installed to remove the air by means of air relief valves, hydrants, or blow-offs when high points cannot be avoided. Automatic air-relief valves may not be used in situations where flooding of the manhole or chamber may occur. The open end of an air-relief pipe shall be extended to the top of a manhole or chamber and have a screened, downward facing elbow equipped with a 24-mesh corrosion resistant screen. If a manhole or chamber vent pipe is installed, the vent pipe shall be metal, terminate downward facing a minimum of 24 inches above grade, and be covered with a rodent screen. Air-vacuum and air relief valves and associated discharge piping shall meet the requirements under s. NR 811.37 (5) (a).

NR 811.72(2)(2) Chambers. Chambers, pits, and manholes containing valves, blow-offs, meters, or other such appurtenances constructed for use in the distribution system shall meet the following requirements:

NR 811.72(2)(a)(a) Location not subject to flooding or high groundwater. If possible, chambers, pits, and manholes containing valves, blow-offs, meters, or other such appurtenances to a distribution system shall not be located in areas subject to flooding or in areas of high groundwater. If location in areas not subject to flooding or in areas of high groundwater is not possible, any valve discharge or structure vent pipes shall terminate a minimum of 24 inches above the ground surface or the high water level, whichever is the higher elevation.

NR 811.72(2)(b)(b) Means to allow drainage. Chambers, pits, and manholes containing valves, blow-offs, meters, or other such appurtenances to a distribution system may not be connected directly to any storm drain or sanitary sewer, nor may any blow-offs or air-relief valves be connected directly to any sewer. Chambers shall be drained to absorption pits underground or to the ground surface where they are not subject to flooding by surface water or high groundwater. If electrical power is available, sumps with sump pumps discharging above grade with a down-turned metal pipe and a free air break over grade or over a storm sewer receptacle may also be approved by the department.

NR 811.72(2)(c)(c) Installation requirements. If not installed in the road right-of-way or if installed in the road right-of-way in areas with minimal risk from damage due to traffic and maintenance equipment, larger below grade facilities or below grade facilities housing pumps and other electrical equipment shall meet the applicable booster pumping station requirements under s. NR 811.84. In addition, if installed in vulnerable areas of the road right-of-way, the facilities may be constructed with a gasketed, watertight, bolt-down cover at grade if approved by the department.

NR 811.73(1)(1) General requirements. Installation of mains shall be in accordance with AWWA standards in effect at the time of design, manufacturer’s recommended installation procedures, and the requirements of this section.

NR 811.73 NoteNote: A copy of the AWWA standards is available for inspection at the central office of the department of natural resources and may be obtained for personal use from the American Water Works Association, 6666 West Quincy Avenue, Denver, Colorado 80235.

NR 811.73(2)(2) Installation specifications. The specifications for installation of mains shall include provisions for all of the following:

NR 811.73(2)(a)(a) Bedding. Continuous and uniform bedding shall be provided in the trench for all buried pipe. Backfill material shall be tamped in layers around the pipe and to a sufficient height above the pipe to adequately support and protect the pipe. Grossly contaminated soil shall be removed, properly disposed of according to chs. NR 500 to 520 requirements, and replaced with clean material. Clean clay cut-off walls shall be installed to minimize the movement of contaminants along the trench if required by the department.

NR 811.73(2)(c)(c) Testing. Pressure testing of the installed pipe, including measurement of leakage and testing for electrical conductivity shall be conducted, if appropriate. Pressure and leakage testing shall be in accordance with AWWA Standard C600 in effect at the time of testing.

NR 811.73(2)(d)1.1. ‘Disinfection required.’ Water mains shall be disinfected before being put into service or before being returned to service following maintenance or repair work. Detailed procedures for disinfection, equivalent to those outlined in AWWA Standard C651 in effect at the time of disinfection, shall be written into the specifications by the design engineer.

NR 811.73(2)(d)2.2. ‘Bacteriological sampling.’ Disinfection and bacteriological sampling requirements shall meet the requirements of s. NR 810.09 (4). The design engineer shall include detailed procedures for bacteriological sampling in the specifications.

NR 811.73(2)(d)3.3. ‘Allowable chlorine in wasted water.’ Consideration shall be given to the amount of chlorine in any water wasted from a water main to the environment to prevent harmful impacts. Dechlorination prior to discharge may be necessary in some cases to prevent harmful impacts. Water wasted to surface water may not contain any substances in concentrations that adversely affect the water as determined under chs. NR 105 and 106. For chlorine, no total residual chlorine may be measured in water being discharged to surface water.

NR 811.73(2)(e)(e) Cover. Sufficient earth or other suitable cover shall be provided over mains to prevent freezing. A minimum cover of 5 feet is required unless determined by the department to be unnecessary in specific cases. Insulation may be required at some installations to prevent freezing.

NR 811.73 NoteNote: The department recommends a minimum depth of cover of 6.5 feet. To assure water mains are installed to prevent freezing, consideration should be given to site specific conditions, such as water demand in the area, frost and groundwater depth, and water mains constructed under streets, highways, or other non-soil surfaces.

NR 811.73(2)(g)(g) Locating wire. All underground components of public water mains, including mains, hydrant leads, and water services to be constructed of nonconductive material, shall be provided with a locating wire or other department approved equally effective means that can be used to locate the components.

NR 811.73(3)(3) Pipe bursting. Department approval is required prior to installing any replacement water mains using the pipe bursting method. Replacement water mains installed through the pipe bursting method shall meet the following requirements in addition to the applicable requirements of sub. (2).