Gravel wetland systems shall comply with the following:
- (a) The system shall be designed in accordance with “UNHSC Subsurface Gravel Wetland Design Specifications”, January 2022, available as noted in Appendix B, unless otherwise specified;
- (b) Pretreatment as described in Env-Wq 1508.12 through Env-Wq 1508.16 shall be provided if stormwater, other than roof runoff, will be discharged to the practice;
- (c) The system, excluding the saturated zone but including any sediment forebays, shall be designed to completely drain within 72 hours; and
- (d) The system shall have 2 treatment bays, each of which is designed to filter at least 45% of the WQV with a minimum flow path of 15 feet, or one treatment bay designed to filter at least 90% of the WQV with a minimum flow path of 30 feet.
Source. #12342, eff 8-15-17 (formerly in Env-Wq 1508.04(f) in #9817-A, eff 12-1-10); ss by #13758, eff 9-28-23; ss by #14472, eff 1-19-26, EXPIRES: 1-19-36