Section NR 811.66 - Distribution system storageThe applicable design standards of ss. NR 811.63 and shall be 811.64 followed for distribution storage. In addition:
(1) PRESSURE VARIATION. Distribution system storage facilities shall meet all the following requirements: (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.(b)Minimum and maximum pressures. The minimum and maximum pressure in service areas shall be 35 and 100 psi respectively at ground level. 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.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. 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.
(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).(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.Wis. Admin. Code Department of Natural Resources NR 811.66
CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.