§ 19.1-03.4 Selecting SMPs Using the SMP Hierarchy.
RCNY § 19.1-03.4
(a)SMPs must be selected, using the SMP hierarchy, as follows, and as more fully described in the NYC Stormwater Manual: (1) Vegetated retention practices must be used, to the maximum extent practicable to meet requirements.
(2)Where vegetated retention practices are not possible or cannot meet the entire runoff reduction volume due to site constraints, the site constraints must be documented in the SWPPP and non-vegetated retention practices must be used, to the maximum extent practicable to meet requirements.
(3)Where both vegetated and non-vegetated retention practices are not possible or cannot meet the entire runoff reduction volume due to site constraints, the site constraints must be documented in the SWPPP and: (i) In the combined sewer service area, any remaining requirements must be met using either vegetated or non-vegetated detention practices; (ii) In the MS4 area, any remaining requirements must be met using either vegetated or non-vegetated treatment practices.
(b)When SMPs are deemed infeasible due to site constraints, including soil, subsurface, "hotspot," surface and space constraints, the designer must provide the appropriate documentation that demonstrates each constraint.
(c)All documentation for constraints and justification for the selection of practices must be included in the SWPPP and are subject to review and approval by the Department. (Added City Record 2/15/2022, eff. 2/15/2022)
