A.
On any parcel upon which new construction involving the creation of more than 500 square feet of new impervious surfaces will be created or, in the determination of the Building Inspector, significant additional runoff will be generated, the owner of the parcel shall be required to provide on-site water retention facilities meeting not less than the following criteria.
(1)
Impervious surfaces. For all new impervious surfaces, the owner shall provide on-site water retention facilities for the full volume of 100% of a five-inch rainfall.
(2)
All other surfaces. For all other surfaces, the owner shall provide on-site water retention facilities for the full volume of 30% of a five-inch rainfall, as a minimum. Factors to be considered which may warrant an increase in this percentage may include soil conditions, the type of surface coverage, groundwater conditions, and site slope.
B.
In situations of extreme slopes, grade raises, or other unusual conditions, the Building Inspector and/or the Village Engineer may require greater on-site water retention facilities in order to protect adjacent properties, public roads, and/or waterways and other wetlands.
C.
In any land development application before it, the Board of Trustees, the Planning Board, the Board of Appeals, the Architectural and Preliminary Site Review Board, and the Landmarks Preservation Commission may require greater on-site water retention facilities in order to protect adjacent properties, public roads, and/or waterways and other wetlands.
[Amended 11-20-2017 by L.L. No. 6-2017]