NR 811.64(16)(c)
(c) Valve vaults and above grade enclosures. Valve vaults and above grade enclosures installed at the base of storage facilities shall be protected against freezing and provided with floor drainage. Floor drains may be connected to a sanitary sewer, when available, if the floor elevation is at least one foot above the rim elevation of the nearest upstream sanitary sewer manhole. If a sanitary sewer is available but a manhole is not located nearby or the manhole does not comply with the upstream location or the one-foot requirement, the department may require installation of an additional manhole on the sanitary sewer main or on the sanitary building sewer. The facility may discharge to the ground surface by gravity, if possible, or else by a floor sump with a sump pump permanently installed. If constructed outside of the storage facility, the entrance to the vault or enclosure shall be locked to prevent unauthorized access.
NR 811.64(16)(d)
(d)
Condensate platform drains. Condensate platform drains shall not be directly connected to the overflow piping. The condensate platform drain shall be a minimum 2-inch diameter pipe and shall be brought down to within 12 to 24 inches of the ground surface and discharge downward facing with a free air break over a drainage inlet structure, splash pad, or riprap.
NR 811.64(17)
(17)
Disinfection. Water storage structures shall be disinfected in accordance with all the following requirements:
NR 811.64(17)(a)
(a) Disinfection required. Water storage structures shall be disinfected before being put into service or before being returned to service following maintenance or repair work to the water storage structure. Detailed procedures for disinfection, equivalent to those outlined in AWWA standard C652 in effect at the time of disinfection, shall be written into the specifications by the design engineer or contractor as applicable.
NR 811.64(17)(b)
(b) Bacteriological sampling. Disinfection and bacteriological sampling requirements shall meet the requirements of s.
NR 810.09 (4). Detailed procedures for bacteriological sampling shall be written into the specifications by the design engineer or contractor as applicable.
NR 811.64(17)(c)
(c) Allowable chlorine in wasted water. The amount of chlorine in any water wasted from a storage structure to the environment shall be assessed 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 a surface water.
NR 811.64 Note
Note: 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 811.64 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10; correction in (11) (e), (f) made under s.
13.92 (4) (b) 7., Stats.,
Register December 2011 No. 672;
CR 22-074: am. (1) (a), (3) (a) 2., 3., (4) (a) 1., 3., 5., cr. (4) (a) 6., 7., r. (4) (c) 1., renum. (4) (c) 2. to (4) (c), am. (4) (d) 1., (7) (a), (b), (8) (c), cr. (8) (f) 4., am. (10) (i), r. (16) (b), am. (16) (c), cr. (16) (d) Register January 2024 No. 817, eff. 2-1-24; correction in (4) (a) 6. made under s. 35.17, Stats., Register January 2024 No. 817. NR 811.65
NR 811.65 Plant storage. The applicable design standards of ss.
NR 811.63 and
811.64 shall be followed for plant storage. In addition:
NR 811.65(1)
(1)
Filter washwater tanks. Filter washwater tanks shall be sized, in conjunction with available pump units and finished water storage, to provide the backwash water required by s.
NR 811.49. The design shall address the possibility of having to backwash more than one filter at a time, or several filters in succession.
NR 811.65(2)(a)(a) Clearwell storage shall be sized, in conjunction with distribution system storage, to relieve the filters from the strain of fluctuations in water use or peak demands.
NR 811.65(2)(b)
(b) When water storage is used to provide proper contact time for disinfection, documentation, including tracer testing, shall be provided to assure adequate detention time under all operating conditions. The department may require the installation of baffle walls or additional reservoir capacity if necessary to prevent short circuiting and to obtain adequate contact times.
NR 811.65(3)
(3)
Basins and wet-wells. Receiving basins, pump cans, and pump wet-wells for finished water or water to become finished water shall be designed as finished water storage structures.
NR 811.65 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10.
NR 811.66
NR 811.66 Distribution system storage. The applicable design standards of ss.
NR 811.63 and
811.64 shall be followed for distribution storage. In addition:
NR 811.66(1)
(1)
Pressure variation. Distribution system storage facilities shall meet all the following requirements:
NR 811.66(1)(a)
(a) Allowable head range. The maximum variation between high and low levels in storage structures which float on a distribution system may not exceed 30 feet during normal usage.
NR 811.66(1)(b)
(b) Minimum and maximum pressures. The minimum and maximum pressure in service areas shall be 35 and 100 psi respectively at ground level.
NR 811.66(1)(b)1.
1. In areas where a minimum of 35 psi cannot be maintained, a high pressure zone shall be established in the distribution system by means of booster pumps and related facilities or pressure boosting systems on individual service lines as required in subch.
XI. The use of individual service line booster pumps shall be limited to the extent possible.
NR 811.66(1)(b)2.
2. In situations where static pressures exceed 100 psi, pressure reducing devices may be required on mains in distribution systems having documented system deficiencies or problems due to high pressure such as main breaks and service line breaks.
NR 811.66 Note
Note: Section
SPS 382.40 (7) (d) 2. a. requires a pressure reducing device to be installed to protect individual services when the incoming pressure exceeds 80 psig.
NR 811.66(2)
(2)
Drainage. The design shall allow draining of storage facilities for cleaning or maintenance while maintaining adequate positive pressure in the distribution system. The drains shall discharge to the ground surface as required in s.
NR 811.64 (3).
NR 811.66(3)
(3)
Level controls. Adequate controls shall be provided to maintain required levels in distribution system storage structures. Level indicating devices shall be provided at a central location. Combination indicating and recording devices are recommended.
NR 811.66 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10.
NR 811.67
NR 811.67 Applicability. This subchapter covers water distribution systems for community water systems which are to be located in street rights-of-way or easements. Other piping systems shall be constructed in accordance with the requirements of ch.
SPS 382.
NR 811.67 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10; correction made under s.
13.92 (4) (b) 7., Stats.,
Register December 2011 No. 672.
NR 811.68
NR 811.68 Ownership of municipal water distribution systems. NR 811.68(1)(1)
Municipal ownership. The distribution system of a municipal water system shall be owned and maintained by the waterworks owner.
NR 811.68(2)
(2)
Municipally owned mains on private property. All water mains and other distribution system components owned by a municipal water system on private property shall be installed in permanent easements.
NR 811.68 Note
Note: To assure the use of approved materials and proper installation and maintenance, the department recommends that fire hydrants and water mains to be constructed on private property be installed in permanent easements and owned and maintained by the waterworks owner.
NR 811.68(3)
(3)
Privately owned looped mains and private water services requiring check valves. Water mains and water services to be connected to the publicly owned distribution system at more than one point may be privately owned and maintained provided that a check valve is installed on the water main at each point of connection to the distribution system to prevent water from flowing back into the distribution system. Each check valve shall be located in a manhole or vault and shall be immediately preceded and followed by a buried or exposed shut-off valve on the main. The water supplier shall have access to the manholes and valves for inspection purposes.
NR 811.68 Note
Note: A drain fitting may be added on the piping between the check valve and the gate valve on the public water system side of the check valve. The gate valve may be closed and the drain fitting opened to periodically check for leakage through the check valve. Refer to s.
SPS 382.40 for standards for the construction of private water mains.
NR 811.68 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 22-074: am. (2), (3) Register January 2024 No. 817, eff. 2-1-24. NR 811.685
NR 811.685 Interconnections with other water sources. A water system owner shall obtain department approval prior to any interconnections between a public water supply system and another source of water in accordance with s.
NR 810.15 (2), including interconnections solely for emergency backup purposes.
NR 811.685 History
History: CR 22-074: cr. Register January 2024 No. 817, eff. 2-1-24. NR 811.69
NR 811.69 Materials. Water main materials shall meet the following requirements:
NR 811.69(1)
(1)
Acceptable materials. All pipe used for water main installations shall be cast iron, ductile iron, steel, reinforced concrete, polyvinyl chloride, high density polyethylene, copper, or materials specially approved by the department for restricted or experimental use. If a restricted or experimental use approval is issued, the department may require special precautions until a satisfactory use record has been established. For polyvinyl chloride pipe, the pipe shall have a maximum dimension ratio of 18 and only joints with elastomeric gaskets or butt fusion welds shall be used.
NR 811.69(2)
(2)
Standards. Pipes, joints, fittings, valves, and fire hydrants shall have been manufactured in conformity with the latest standards issued by the AWWA and may not be used unless approved by the department. All pipe shall be minimum AWWA pressure class 150 and shall be designed for a minimum 100 psi working pressure except as approved by the department for special low pressure applications. Specifications for water main pipe and joints for water mains having a diameter less than those contained in AWWA standards shall meet the requirements of s.
SPS 382.40.
NR 811.69 Note
Note: 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 811.69(3)
(3)
Lead free. Any pipe, pipe fittings, solder, or flux used in the installation or repair of any public water system shall be lead free. “Lead free” means, with respect to solders and flux, containing not more than 0.2 percent lead and, with respect to pipes and pipe fittings, containing not more than 0.25 percent lead. Repairs to lead joints shall be made using alternative methods, if possible. For ductile iron pipe, the use of lead tipped gaskets is prohibited.
NR 811.69(4)
(4)
Protection against corrosion. Special attention shall be given to selecting pipe materials which will protect against internal and external corrosion. If soils, groundwater, or both, are aggressive, ductile iron water mains shall be provided with polyethylene encasement installed in conformity with the latest AWWA standards.
NR 811.69(5)
(5)
Protection against contamination from organic compounds in soil and groundwater. If possible
, construction of water mains through or near areas of soil or groundwater contamination shall be avoided. Special attention shall be given to selecting pipe and gasket materials for construction in contaminated soil or groundwater which will protect against external corrosion and penetration of the pipe and gaskets by the contaminants.
Water mains designed to pass through or near areas of contaminated soil or groundwater shall meet the following requirements:
NR 811.69(5)(a)
(a) The department shall be contacted to obtain approval of the water main design requirements prior to the submittal to the department of the plans and specifications.
NR 811.69(5)(b)
(b) Installations shall meet the following design criteria:
NR 811.69(5)(b)1.
1. Minimum class 52 ductile iron water main piping with polyethylene encasement shall be used.
NR 811.69(5)(b)2.
2. Hydrant drain ports shall be permanently plugged or hydrant barrels installed without drain ports.
NR 811.69(5)(b)4.b.
b. The soil or groundwater contamination exceeds primary drinking water standards.
NR 811.69(6)
(6)
Rehabilitation. All materials used for the interior rehabilitation of water mains shall meet ANSI/NSF standards and may not be used until specifically approved by the department.
NR 811.70
NR 811.70 Water main design. The design of water mains and distribution systems shall meet the following requirements:
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 Note
Note: 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 Note
Note: 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 Note
Note: 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 Note
Note: 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 Note
Note: 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:
-
See PDF for table 
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 History
History: 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 History
History: 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 811.72
NR 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.
