The design standards for storm water runoff facilities for Zones A, B and C, as described in Section 1043.42, are the following:
Zone A | Zone B | Zone C | |
Criteria | High quality waters. Meets water quality standards. Less than 10% imperviousness. | Degraded physical, biological or water quality indicators. 10% to 25% imperviousness. | Heavily degraded physical, biological or water quality indicators. Greater than 25% imperviousness. |
Storm Water Management Standards | Use infiltration basins, infiltration trenches, extended detention basins, and/or constructed wetlands. Maintain and enhance buffer strips. | Use detention ponds, maintain and enhance buffer strips, and reduce directly connected impervious area. | Use sediment basins, maintain and enhance buffer strips and reduce directly connected impervious area. |
Water Quality Control | Detain the first 0.5" of runoff from the contributing watershed, with detention per Zone B and infiltration where conditions permit, or provide equivalent treatment. | Detain the first 0.5" of runoff from the contributing watershed for 24 hours or provide equivalent treatment. | Provide sedimentation control within the drainage system. |
Bank Erosion Control | Rate of release shall be limited to 0.05 cfs/acre for a 2-year storm event. | None | Storm water runoff shall not exceed the capacity of the downstream conveyance system. |
Flood Control | Detention with infiltration when conditions permit. Release rate of 0.13 cfs/acre per KCDC rules. | Release rate of 0.13 cfs/acre per KCDC rules. | Direct conveyance of storm water runoff with the capacity of downstream system. |
(Ord. 07-2002-10. Passed 7-2-02.)