(A) The Drainage Board may, as a prerequisite to issuance of a storm water permit, require the dedication of easements to the town and to owners of other affected lands by the owner of the parcel of land relative to which application for a storm water permit has been made, where necessary to achieve satisfactory present and future drainage of the parcel and the area surrounding the parcel.
(B) Provisions concerning these easements are as follows:
(1) Easements shall be required for areas that drain greater than 5 acres of storm water runoff which are adjacent to the parcel in question but not under the same ownership.
(2) These easements shall be accessible to vehicular traffic.
(3) Easements along a public right-of-way shall be contiguous with and accessible from the right-of-way. The granting of a drainage easement to the town does not create a responsibility for the town to maintain the drainage facilities located within the easement area.
(4) The town shall be under no obligation to accept a dedication from the subdivider, developer or owner of any of the storm water detention facilities, ponds or areas; but the town, in the exercise of its sole and exclusive discretion, may require the subdivider, developer or owner to so dedicate the facilities, ponds or areas to the town. In the event that no such dedication is required, the subdivider, developer and/or owner shall be required to submit to the town written evidence in the form of covenants, conditions or restrictions that run with and become a charge against the land providing for the perpetual maintenance of the storm water retention facilities, ponds or areas at no cost to the town in form and content acceptable to the town, which covenants, conditions and restrictions the town is hereby authorized to record with the appropriate County Recorder of Deeds as and for permanent evidence of that obligation to maintain.
(5) Detention/retention basins shall be constructed within a storm water easement either platted or legally described and recorded as a perpetual storm water easement, a minimum of 20 feet horizontally outside of the design 100-year floodwater elevation of the basin. All detention/retention basins shall be maintained according to original design capacity.
(6) Guidelines for minimum easement widths for swales and ditches are provided below. A hydraulic and hydrologic computation must be performed to determine the inundated area of the 25-year storm. The easement must protect the entire 25-year flood area. For drainage areas larger than 5 acres, an analysis must be performed for the 100-year storm event. A 100-year storm event flood line must be added to the 25-year easement restriction. The lowest location of any adjacent structures where water may enter must be outside the 100-year storm event plan view.
(a) Residential collector swales.
1. Surface water collector swales within the rear yard and side yard areas of residential subdivisions shall be constructed within a drainage easement possessing a minimum width of 20 feet, with the drainage swale constructed approximately in the middle of the easement.
2. Surface water collector swales within commercial and industrial developments will not be required to be constructed within a storm water easement, provided only minimal quantities of off-site surface water flows are required to enter the channel. Minimal quantities shall mean less than 5 acres of land area. Collector swales within commercial and industrial developments which collect 5 acres or more of off-site land area shall be constructed within a storm water easement possessing a minimum width of 20 feet.
(b) Open ditches. Existing open ditches which are to be perpetuated through the developing property and newly constructed open ditches shall be placed within a drainage easement of a minimum width of 20 feet from the tops of banks of the channel. All ditches shall be maintained according to original design capacity.
(7) (a) Minimum easement widths for storm drains are as provided below. More stringent requirements for storm water easement size and additional covenants may be made by the Department based upon individual site conditions.
(b) Storm drain easement widths are as follows:
Depth of Drain, from Finish Grade to Crown
|
Diameter of Storm Drain | Minimum Easement Width |
3 feet or less | 15 inches or less | 15 feet |
More than 3 feet | 15 inches or less | 20 feet |
3 feet or less | Greater than 15 inches | 20 feet |
More than 3 feet | Greater than 15 inches | 25 feet |
(8) An easement for open culverts must be recorded for the 50-year storm event flow areas.
(Ord. 1995-10 § XXIV, passed 10-13-1995)