The function of existing on-site depressional storage shall be preserved for both on-site and off-site tributary flows in addition to required detention. When depressional storage is removed it must be compensated for in the site runoff storage facility at a 1 to 1 ratio provided that offsite areas tributary to the existing depressional storage are routed through the site runoff storage facility. This requirement is in addition to the site runoff storage required in §§ 160.030 through 160.039. The Administrator may allow the function of depressional storage to be preserved if the applicant performs detailed pre- and post-project hydrologic and hydraulic modeling to identify the effect of the depressional storage on discharges over a range of rainfall frequencies.
(Ord. 06-0383, passed 3-15-06; Am. Ord. 19-1532, passed 1-16-19)