(A) (1) The subdivider shall provide the subdivision with an adequate storm water sewer system whenever curb and gutter is installed and whenever the evidence available to the Commission indicates that the natural surface drainage is inadequate.
(2) When the surface drainage is adequate, easements for such surface drainage are permitted along the side of the street, but where curbs and gutters are not provided, a shallow swale of at least a two-foot bottom width and 3:1 side slopes and a depth of at least one foot not to exceed three feet below the finished grade of the road may be permitted.
(3) In all cases the drainage swales must be of adequate size and dimension to handle the drainage in the watershed; provided that, where existing natural drainage ways offer a suitable means of storm drainage, the street right-of-way may be widened to accommodate them, or they may be located in a parkway or easement.
(4) Subsurface drainage of concrete, clay or plastic tile shall be installed in those soils where it is deemed necessary to protect the street from damage because of high water table.
(a) These drains shall be located one foot adjacent to the road bed with a minimum of two feet of cover.
(b) They shall outlet into a storm sewer or open ditch.
(c) The diameter of these subsurface drains shall not be smaller than six inches, nor larger than 12 inches, unless approved by the Commission.
(d) These subsurface drains shall not have surface or storm water inlets.
(e) These subsurface drains shall be bedded in a two-foot by two-foot bed of gravel.
(f) Peak discharge of any drainage system shall be no greater than existed before the land use change.
(B) (1) In a subdivision where curbs and gutters are not provided, to facilitate roadside drainage and to assure suitable entrances for private driveways which are proposed to intersect the roadway, the subdivider shall furnish a metal pipe, at least 12 inches in diameter and 14 feet in length to be placed where required for each driveway.
(2) Where this type of pipe is used, end-sections shall be installed at each end.
(3) The diameter of the pipe shall be of adequate size to dispose of the water in the watershed area.
(Ord. passed 10-19-1977)