(a) General Requirements. The Planning Commission shall not recommend for approval any plat of subdivision which does not make adequate provision for storm or flood water runoff channels or basins. The storm water drainage system shall be separate and independent of any sanitary sewer system. Storm sewers, and any other item, instrument, device, implementation or system related to stormwater management or surface water discharge and/or control, where required, shall be designed so as to meet the requirements for approval as set out in the Stormwater Management and Surface Water Discharge Control Ordinance found in Article 937 of the Vienna Codified Ordinances or its successor ordinance or ordinances.
(b) Dedication of Drainage Easements.
(1) General requirements. Where a subdivision is traversed by a watercourse, drainageway, channel or stream there shall be provided a storm water easement or drainage right of way conforming substantially to the lines of such watercourse, and of such width and construction or both as will be adequate for the purpose. Wherever possible, it is desirable that the drainage be maintained by an open channel with landscaped banks and adequate width for maximum potential volume of flow.
(2) Drainage easements.
A. Where topography or other conditions are such as to make impractical the inclusion of drainage facilities within road rights of way, perpetual unobstructed easements at least fifteen feet in width for such drainage facilities shall be provided across property outside the road lines and with satisfactory access to the road. Easements shall be indicated on the plat. Drainage easements shall be carried from the road to natural watercourse or to other drainage facilities.
B. When a proposed drainage system will carry water across private land outside the subdivision, appropriate drainage rights must be secured and indicated on the plat.
C. The applicant shall dedicate, either in fee or by drainage or conservation easement of land on both sides of existing watercourses, to a distance to be determined by the Planning Commission.
D. Low-lying lands along watercourses subject to flooding or overflowing during storm periods, whether or not included in areas for dedication, shall be preserved and retained in their natural state as drainage ways. Such land or lands subject to periodic flooding shall not be computed in determining the number of lots to be utilized for average density procedure nor for computing the area requirement of any lot.
(Ord. 10-14. Passed 8-14-14.)