Section 811.62. Volume and pressure.

 

(1)   Volume requirements. A sufficient quantity of water, as determined from engineering studies, shall be maintained in elevated storage when only one pumping unit to the distribution system is available to serve the water system. This shall be at least an average-day supply under normal operating conditions. When more than one distribution pump is available, the storage shall be in accordance with standard engineering practice. Standard engineering practice is based upon an engineering review of existing and future water supply needs including: type of service and population served; average day, maximum day, peak hour and fire flow demands and durations; water source quality, availability and treatment, pump capacities, auxiliary power, storage capacity, water distribution and costs.

(2)   Pressure requirements. Storage facilities shall be designed to meet all the following requirements:

(a) Minimum and maximum pressures. The storage facilities shall be designed to meet the minimum and maximum pressure requirements specified in s. NR 811.66 (1) .

(b) Fire flows and residual pressures. When fire protection is to be provided, the storage facilities shall be designed in conjunction with distribution system design to provide the minimum fire flows and residual pressures specified in s. NR 811.70 (6) .

(c) Alternative means for maintaining pressure. A hydro-pneumatic tank, booster pumping facilities, or other reliable means shall be provided to maintain system pressure when a gravity storage reservoir or tank is not available.

(3)   Elevated storage requirement waived. The department may waive the requirement for elevated storage if the system is designed to serve less than 50 homes, if it is not economically feasible to provide elevated storage, if elevated storage facilities are proposed for a later development phase, or if service is proposed for domestic use only.

History: CR 09-073 : cr. Register November 2010 No. 659 , eff. 12-1-10.