Wis. Admin. Code Department of Natural Resources NR 811.73

Current through September 30, 2024
Section NR 811.73 - Installation of mains
(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.

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.

(2) INSTALLATION SPECIFICATIONS. The specifications for installation of mains shall include provisions for all of the following:
(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.
(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.
(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.
(d)Disinfection and sampling. All new, cleaned or repaired water mains shall be disinfected and sampled in accordance with the following requirements:
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.
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.
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.

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.

(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.

Note: 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.

(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.
(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.
(h)Erosion control. Construction site erosion control shall be provided in accordance with s. NR 811.09 (2).
(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).
(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).
(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.
(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.

Wis. Admin. Code Department of Natural Resources NR 811.73

CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.
Amended by, CR 22-074: am. (2) (e) Register January 2024 No. 817, eff. 2/1/2024