Agenda - Council - 05/13/2014 - Laserfiche WebLink

Home

7080.2050 INDIVIDUAL SUBSURFACE SEWAGE TREATMENT SYSTEMS 40 the distribution box must not result in surfacing of sewage from the box. Pressure must not build up in the box during pump discharge. E. Nonpressurized distribution pipes must meet the requirements of subitems (1) to (4) and subpart 2, item B, subitems (1) and (3) to (5). (1) Distribution pipes used for gravity distribution must be at least four inches in diameter. (2) Distribution pipes used for gravity distribution must have at least one row of holes of no less than one-half inch in diameter spaced no more than 40 inches apart. (3) Distribution pipes for gravity distribution must be laid level or on a uniform slope oriented away from the distribution device of no more than four inches per 100 feet. (4) Distribution pipes for gravity distribution in seepage beds must be uniformly spaced no more than five feet apart and not more than 30 inches from the side walls of the seepage bed. Subp. 4. Pressure distribution. A. All systems must be pressurized as required in parts 7080.2200 to 7080.2400. B. Pressurized distribution pipes must conform to the requirements of subpart 2, item B, subitems (1) and (3) to (5). C. Pressure distribution pipes and associated fittings must be properly joined together. The pipe and connections must be able to withstand a pressure of at least 40 pounds per square inch. D. The distribution network must be designed so there is less than a ten percent variance in flow for all perforations. E. Perforations must be no smaller than one -eighth inch diameter and no larger than one -quarter inch diameter. The number of perforations, perforation spacing, and pipe size for pressure distribution must be in accordance with Table VI. The friction loss in any individual perforated lateral must not exceed 20 percent of the average pressure head on the perforations. TABLE VI MAXIMUM NUMBER OF PERFORATIONS PER LATERAL 1/4 inch holes Pipe diameter in inches 1 1.25 1.5 2 3 Perforation spacing in feet 2 10 13 18 30 60 2.5 8 12 16 28 54 3 8 12 16 25 52 3/16 inch holes Copyright ©2014 by the Rev so of Statutes, State of Minnesota. All Rights Reserved.