529 STORM WATER MANAGEMENT: REQUIREMENTS

529.1 Before any person develops any land in the District of Columbia, the Department's storm water management criteria shall be met.

529.2 Every applicant shall comply with the following minimum storm water runoff control requirements:

(a) Submit management measures necessary to maintain the post-development peak discharges for a twenty-four hour, two- and fifteen-year frequency storm event at a level that is equal to or less than the respective, twenty-four hour, two- and fifteen-year pre-development peak discharge rate through storm water management practices that control the volume, timing and rate of flows;

(b) Where a development is planned in which the storm water runoff will increase the downstream discharge into an area designated as a flood hazard watershed, as delineated on the National Flood Insurance Flood Hazard Boundary Maps (FHBM), the developer shall complete an analysis of the downstream peak discharge for a one hundred (100) year frequency storm event, and shall install the appropriate controls to avoid exceeding this peak discharge;

(c) Where runoff is discharged into an off-site storm water management facility, the applicant shall provide controls in accordance with those mandated by the Department in the Stormwater Management Guidebook;

(d) Any storm water discharge facility which may receive storm water run-off from areas which may be potential sources of oil and grease contamination in concentrations exceeding ten (10) milligrams per liter (mg/l), shall include a baffle, skimmer, grease trap or other mechanism which prevents oil and grease from escaping the storm water discharge facility in concentrations that would violate or contribute to the violation of applicable water quality standards in the receiving waters of the District;

(e) Any storm water discharge facility which receives storm water runoff from areas used to confine animals and which discharges directly into receiving waters shall be designed to prevent at least eighty-five percent (85%) of the organic animal wastes from escaping the storm water discharge facility. The discharge from the facility shall not violate the water quality standards in the receiving waters of the District; and

(f) All storm water management plans, shall conform to the District of Columbia's erosion and sediment control plans and flood management plans.

SOURCE: Final Rulemaking published at 35 DCR 21, 23 (January 1, 1988).