§ 151.047  DETENTION BASIN OUTLET/CONTROL STRUCTURE DESIGN.
   (A)   Backwater on the outlet structure from the downstream stormwater management system shall be evaluated when designing the outlet.
   (B)   Single pipe outlets shall be a minimum of 12 inches in diameter.
   (C)   Minimum outlet restrictor sizes shall be four inches in diameter, provided there is adequate downstream capacity. Where release rates dictate an outlet orifice less than four inches in diameter, alternative outlet designs which avoid clogging shall be utilized.
   (D)   Outlet pipes and restrictors shall be designed to minimize the possibility of clogging and ease of maintenance, even during high runoff events. A trash rack shall be provided.
   (E)   The outlet design shall not require mechanical or manual adjustment to control flow.
   (F)   The control structure shall be designed to maintain as uniform a flow as possible, independent of the stormwater storage volume. An energy dissipater (such as riprap or a plunge pool) shall be provided to reduce erosive velocities.
(Ord. 07-02, passed 4-16-2007)