(A) Amount of storm water runoff.
(1) No subdivision shall cause adjacent landowners, watercourses, drainageways or channels to receive storm water runoff from the subdivision at a higher peak flow rate, or at higher velocities, than would have resulted from the same storm event occurring within the proposed subdivision site in its existing condition;
(2) The discharge of storm water into irrigation ditches shall not be permitted without approval from the appropriate owner and the town; and
(3) Public water shall not be discharged onto or through private property without a recorded easement from appropriate landowners.
(B) Velocity of storm water runoff. All storm water retention storage, sump storage and groundwater recharge areas shall be located within the subdivision property. These areas shall be designed to contain and dispose of the estimated runoff from 100-year, 24-hour storm event.
(C) Detention basins.
(1) When necessary, detention basins or equivalent management facilities shall be designed and constructed with sufficient capacity to maintain a post-development runoff rate from a subdivision development site that is equal or lower than the pre-development runoff rate. Drainage design shall address the treatment of surface and storm water runoff via both wet-weather and dry-weather discharges.
(2) Where runoff from development of a subdivision could generate adverse consequences upon persons, land or wildlife, storm water detention facilities shall be constructed prior to any earth moving activities associated with site development.
(Prior Code, § 14.02.065) (Ord. 2018-10, passed 8-8-2018)