Storm Drainage Rules for New Subdivisions

General Standards for Drainage.Protect and preserve existing natural drainage channels to the greatest extent feasible.Protect the subdivision from flood hazards.Provide a system by which water within the subdivision will be removed without causing damage or harm to the natural environment, or to property or persons within the subdivision or to adjoining areas.Assure that waters drained from the subdivision are substantially free of pollutants, including sedimentary materials, of any greater quantity than would occur in the absence of subdivision and improvement, in order to protect the watercourses and shorelines.Assure that waters are drained from the subdivision in a manner that they will not cause erosion outside of the subdivision to any greater extent than would occur in the absence of subdivision and improvement, in order to protect the watercourses and shorelines.Provide for the crossing of watercourses by spanning rather than by culverts when possible, so that natural stream beds will not be altered where the alterations will cause undue environmental change.Easements and Rights-of-Way. In the event drainage improvements are made for a subdivision, adequate rights-of-way and easements for storm drainage purposes shall be provided.Oversize Drainage Facilities. The Department of Public Works may require that the applicant design and construct a drainage system that will serve adequately the entire drainage basin within which the subdivision is located when the basin is ultimately developed.