NR 811.70(1)(1) General. Water mains and water distribution systems shall be designed and operated to maintain point-of-entry water quality. Special consideration shall be given to distribution main sizing, providing multidirectional flow when possible, providing an adequate number of shut-off valves for distribution system control, providing an adequate number of fire hydrants where fire protection will be provided, and providing for adequate flushing throughout the system. Systems shall be designed to maximize turnover, to minimize the number of dead ends, and to minimize residence times while delivering pressures and flows meeting the requirements under subs. (4) and (6). NR 811.70(2)(2) Flooding. Any areas of the project which are located within the floodway, as defined in s. NR 116.03 (22), or floodplain as defined in s. NR 116.03 (16), shall be identified on the plans and shall conform to the requirements of that chapter. NR 811.70 NoteNote: Refer to ch. NR 116 for floodway and floodplain requirements. NR 811.70(3)(3) Wetlands. Any areas of the project which are to be located within a wetland, pass through a wetland or may impact a wetland shall be identified. NR 811.70 NoteNote: Copies of the Wisconsin wetland inventory maps are available for inspection at the office of the department of natural resources and may be purchased through the department’s internet web site.
NR 811.70(4)(4) Pressure. All water mains, including transmission mains and those not designed to provide fire protection, shall be sized after a hydraulic analysis based on flow demands and pressure requirements. The minimum and maximum normal static pressure in the distribution system shall be 35 psi and 100 psi, respectively, at ground level. The system shall be designed and operated to maintain a minimum residual pressure of 20 psi at ground level at all points in the distribution system under all conditions of flow. NR 811.70(5)(5) Diameter. The minimum diameter of water mains to provide water for fire protection and to serve fire hydrants is 6 inches. Larger mains are required if necessary to allow the required fire flow while maintaining a minimum residual pressure of 20 psi at ground level at all points in the distribution system. NR 811.70(6)(6) Fire protection. The minimum flow requirement for water mains serving fire hydrants is 500 gpm at 20 psi residual pressure at ground level at all points in the distribution system. NR 811.70 NoteNote: It is recommended that the actual fire flow design be based on the capacity of any fire pumper which may be connected to the water main and the type of services or buildings to be protected. It is also recommended that the local fire department be consulted to discuss needed fire flows before constructing water system improvements.
NR 811.70(7)(7) Small diameter mains. Any departure from minimum requirements shall be justified by hydraulic analysis and future water use, and will be considered for approval by the department only in special circumstances. The main sizing for small diameter mains may be calculated based upon a fixture unit determination. NR 811.70 NoteNote: See the requirements of ch. SPS 382 for guidance in sizing mains according to fixture units to be served. NR 811.70(8)(8) Dead ends. Dead ends shall be minimized by looping mains whenever possible. Where dead end mains occur, they shall terminate with a fire hydrant, if flow and pressure are sufficient, or with an approved flushing hydrant or blow-off for flushing purposes. Flushing devices shall be installed on the dead end of all water main stubs 20 feet or more in length unless a shut-off valve is installed near the point of connection and closed until the stub is placed in service in the future. Flushing devices shall be sized to provide a minimum velocity of 2.5 feet per second in the water main being flushed. Flushing devices on dead end mains shall be installed downstream of all services. No flushing device shall be directly connected to any sewer. NR 811.70 NoteNote: Refer to AWWA standard C651 for required flows and openings to flush pipelines.
NR 811.70(9)(9) Valving. Sufficient valves shall be provided on water mains so that inconvenience or sanitary hazard to water users will be minimized during maintenance and construction. Valves shall be located at not more than 800-foot intervals for distribution system mains. Valves shall not be located at more than 1-mile intervals for transmission mains and shall be located immediately on each side of a distribution system branch. NR 811.70(10)(10) Friction coefficients. Unless other values are specially approved by the department, the following maximum “C” values, using the Hazen-Williams formula, shall be used for checking the hydraulic characteristics of new water mains shown on plans and specifications submitted for review: The “C” value of existing water mains and for all water mains with a pipe diameter of 12 inches or less may be less than the maximum “C” value for new pipe and shall be considered in distribution system analysis. The actual interior diameter of the pipe being modeled shall also be considered in the distribution system analysis.
NR 811.70 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 22-074: am. (1), (4), (9) Register January 2024 No. 817, eff. 2-1-24; correction in (1) made under s. 35.17, Stats., Register January 2024 No. 817. NR 811.71(1)(1) Location. Fire hydrants shall be provided at each street intersection and at intermediate points between intersections. Fire hydrant spacing shall be no more than 600 feet between fire hydrants. NR 811.71(2)(2) Size. Fire hydrants shall have a bottom valve size of at least 5 inches, one 4.5-inch pumper nozzle, and 2 2.5-inch nozzles unless the waterworks has established other hydrant criteria which are in accordance with AWWA standards C502 and C503 in effect at the time of design and are approved by the department. The connecting main between the supply main and the hydrants shall be a minimum of 6 inches in diameter. NR 811.71(3)(3) Restrictions. Fire hydrants may not be installed on proposed water mains which will not have minimum flow and pressure as required in s. NR 811.70 (6). The department may approve the installation of hydrants if system improvements which will make at least 500 gpm available at 20 psi are planned for construction within one year following construction of the proposed improvements. If the department approves the installation of hydrants which do not meet the minimum flow and pressure requirements of s. NR 811.70 (6), the hydrants shall be color coded or tagged and the fire chief shall be notified in writing that fire department pumpers may not be connected to the hydrants until the necessary additional improvements are made and fire flow tests have shown that greater than the minimum required flow and pressure are available. NR 811.71(4)(4) Drains. Hydrant drains may not be connected to, or located within 8 feet of sanitary sewers, storm sewers, or storm sewer inlets. If groundwater rises above the drain port, hydrant drain ports shall be permanently plugged prior to installation or hydrants with no drain ports installed and hydrant barrels shall be pumped dry during freezing weather. If hydrant drain ports are not plugged, a gravel pocket or dry well shall be provided unless the department finds that the natural earth will provide adequate drainage. NR 811.71(5)(5) Auxiliary valves on hydrant leads. Auxiliary valves shall be installed on all hydrant leads. NR 811.71(6)(6) Service laterals on hydrant leads prohibited. Service laterals may not be installed on hydrant leads. 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 811.71 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 22-074: am. (1), (5), (7) Register January 2024 No. 817, eff. 2-1-24. NR 811.72NR 811.72 Air-relief facilities and valve and meter chambers. 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 811.72 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 22-074: am. (1), (2) (c) Register January 2024 No. 817, eff. 2-1-24. 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)(b)(b) Stone removal. Stones found in the trench shall be removed for a depth of at least 6 inches below the bottom of the pipe. 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)(d) Disinfection and sampling. All new, cleaned or repaired water mains shall be disinfected and sampled in accordance with the following requirements: 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 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)(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)(f)(f) Thrust restraint. All tees, bends, plugs and hydrants shall be provided with thrust blocking, tie rods, or a joint restraint system designed to prevent movement. 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). NR 811.73(3)(a)(a) The interior of the water mains shall be thoroughly cleaned of any debris and thoroughly disinfected prior to installation. Water samples shall be collected from the newly installed replacement water mains and sampled for bacteriological quality in accordance with s. NR 810.09 (4). NR 811.73(3)(b)(b) The installed water mains shall be tested to meet at minimum the applicable AWWA pressure and leakage test requirements in effect at the time of testing prior to being placed in service. NR 811.73(3)(c)(c) Unless department approval is obtained for the use of other pipe materials, only butt fused DR 9 or 11 HDPE pipe, butt fused DR 14 or 18 PVC pipe or properly restrained ductile iron pipe shall be used for installation as part of the pipe bursting process. NR 811.74NR 811.74 Separation of water mains and sanitary or storm sewer mains. NR 811.74(1)(1) General. The following factors shall be considered in planning separation of water and sewer mains: materials and type of joints for water and sewer pipes, soil conditions, service and branch connections into the water main and sewer line, compensating variations in the horizontal and vertical separations, space for repair, and alterations of water and sewer pipes. NR 811.74(2)(2) Horizontal separation. The following horizontal separation requirements shall be met: NR 811.74(2)(a)(a) Water mains shall be laid at least 8 feet horizontally from any existing or proposed sanitary sewer main, storm sewer main, or sanitary or storm sewer manhole. The distance shall be measured center to center. NR 811.74(2)(b)(b) In cases where it is not practical to maintain an 8-foot horizontal separation distance, the department may allow exceptions to that requirement on a case-by-case basis, if supported by data from the design engineer. The following requirements shall be met in order for the department to approve a center to center horizontal separation distance of less than 5 feet: NR 811.74(2)(b)1.1. The bottom of the water main shall be at least 18 inches above the top of the sewer main and the minimum horizontal separation distance shall be 3 feet measured edge to edge. NR 811.74(2)(b)2.2. A profile of the rock surface as determined from exploration shall be shown on the plan when high bedrock is the reason for the exception to the 8-foot separation distance. NR 811.74 NoteNote: See Figure No. 10 in the Appendix.
NR 811.74(3)(3) Vertical separation. If water mains cross over sanitary or storm sewer mains, the water main shall be laid at such an elevation that the bottom of the water main is at least 6 inches above the top of the sewer main. If water mains cross under sanitary or storm sewer mains, a minimum vertical separation distance of 18 inches shall be maintained between the top of the water main and the bottom of the sewer main. At crossings, one full length of water pipe shall be centered above or below the sewer so that both joints will be as far from the sewer as possible. Special structural support for the water and sewer pipes may be required by the department after a determination that added support is necessary to meet the requirements of this chapter. NR 811.74(4)(4) Exception. If it is not possible to obtain the proper horizontal and vertical separation as specified in subs. (2) and (3), a gravity sanitary or storm sewer main shall be constructed of materials and with joints that are equivalent to water main standards of construction from manhole to manhole and air pressure tested to assure water tightness in accordance with the 4 psi pressure testing requirements given in s. NR 811.12 (5) (d) 2. Department approval is required for any exception to the requirements in subs. (2) and (3). NR 811.74(5)(5) Force mains. No exception to the 8-foot separation distance may be granted for sanitary sewer force main installations unless the requirement in sub. (2) (b) is met. NR 811.74(6)(6) Sewer manholes. No water pipe may pass through or come into contact with any part of a sanitary or storm sewer manhole. NR 811.74 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10. NR 811.75NR 811.75 Separation of water mains and other contamination sources. NR 811.75(1)(1) Proposed water mains shall be adequately separated from any potential source of contamination. The following minimum horizontal separation distances shall be maintained: NR 811.75(1)(ag)(ag) Three feet between a water main and a stormwater collection system treatment unit, such as a bioswale or permeable paver system. NR 811.75(1)(ar)(ar) Eight feet between a water main and a POWTS holding, treatment, or dispersal component, sanitary sewer lift-station, grave site, stormwater detention pond, retention pond, or infiltration basin. NR 811.75(1)(b)(b) Twenty-five feet between a water main and a buried main or tank containing gasoline, diesel, bio-diesel, ethanol, other alternative fuel, fuel oil, petroleum product, motor fuel, burner fuel, lubricant, waste oil, or hazardous substance. NR 811.75(1)(c)(c) Fifty feet between a water main and a sanitary landfill or agricultural, industrial, commercial, or municipal wastewater treatment plant treatment unit, lagoon, or storage structure. NR 811.75 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 22-074: renum. (1) (a) to (1) (ar) and am., cr. (1) (ag), am. (1) (c) Register January 2024 No. 817, eff. 2-1-24. NR 811.76NR 811.76 Surface water crossings. Surface water crossings, whether over or under water, present special problems. For this reason, the department shall be consulted before final plans are prepared. The design shall meet the following requirements: NR 811.76(1)(a)(a) The pipe shall be adequately supported and anchored, protected from damage and freezing, and accessible for repair or replacement. NR 811.76(1)(b)(b) A means to accommodate bridge expansion such as an expansion joint shall be provided to the water main if the corresponding bridge has expansion joints. NR 811.76(1)(c)(c) Shut-off valves shall be provided at both ends of a bridge crossing if the bridge has expansion joints so that the section can be isolated for testing or repair. The valves shall be easily accessible and not subject to flooding. NR 811.76(2)(a)(a) A minimum cover of 2 feet shall be provided over the pipe. NR 811.76(2)(b)(b) When crossing water courses which are greater than 15 feet in width, the following shall be provided: NR 811.76(2)(b)1.1. The pipe shall be of special construction, having flexible, watertight joints. Butt fused DR 9 or 11 HDPE pipe or butt fused DR 14 or 18 PVC pipe are an acceptable alternative. NR 811.76(2)(b)2.2. Shut-off valves shall be provided at both ends of water crossings so that the section can be isolated for testing or repair. The valves shall be easily accessible, and not subject to flooding, and the valve closest to the supply source shall be in a manhole. Unless the department approves an equivalent method, permanent taps shall be made on the pipe within the manhole on either side of the valve to allow insertion of a small water meter to determine leakage during system pressure testing. NR 811.76 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10. NR 811.77NR 811.77 Common casing crossings. In some cases, such as highway crossings, it becomes desirable due to extremely high construction costs to install water mains, sanitary sewers, force mains or storm sewers within a common casing. The following requirements apply:
