NAC445A.6707. Storage structures: Clear wells.

     1. Clear wells must be sized in conjunction with any distribution storage in such a manner that the components of the public water system for the acquisition and treatment of water will not be required directly to follow fluctuations in the use of water or directly to meet maximum day demand and peak hour demand.

     2. The capacity of a clear well must be sufficient to provide for the storage of the amount of finished water required for:

     (a) Backwashing;

     (b) Equalizing the storage of water necessary for the high-service pumping station of a treatment facility; and

     (c) The operation of a treatment facility, if necessary.

     3. Finished water must not be stored or conveyed in a compartment that is adjacent to a compartment of untreated water unless the two compartments are separated by more than a single wall.

     4. If a clear well is used to provide the period of contact required for disinfection, the clear well must be designed in such a manner that it is of the appropriate size and has such baffles as are necessary to accomplish that function.

     5. Clear wells must be designed in such a manner as to assist the public water system in maintaining its total capacity when filters or processes for treatment fail.

     (Added to NAC by Bd. of Health, eff. 2-20-97)