(A) A storm water sewer system or a surface drainage system designed for not less than a five-year storm frequency to serve the area being subdivided shall be provided.
(B) When curbs and gutters are provided or when the Commission determines the natural surface drainage to be inadequate, the subdivider shall construct a storm water sewer system with inlets appropriately spaced in the subdivision.
(C) A natural surface drainage system shall be permitted when curbs and gutters are not provided, and the natural drainage will, in the opinion of the Commission, adequately drain the storm waters from the subdivision. The drainage should be shallow swales sowed in grass rather than deep, open ditches. Streets not having curbs and gutters shall provide the following:
(1) Side ditch swales constructed at one foot vertical to three feet horizontal.
(2) A swale or culvert at all driveways sized according to amount of storm water flow.
(3) Culverts under the roadway where necessary. Size of culvert to be according to amount of storm water flow but not less than 12 inches.
(4) Relief of side ditches and swales along the roadway through the use of off-street detention basins or existing drainage channels. Detention basins may be required to avoid overloading channels, ditches, etc.
(5) When topsoil has been removed from the surface of a lot on a slope where erosion will cause a displacement of loose materials, the subdivider shall utilize approved methods to prevent the wash from damaging adjacent property.
(6) In the design of a storm sewer system for each subdivision, the present and future expected runoff from the larger drainage area shall be considered. If sewers larger than those necessary to service the subdivision alone are recommended, then the Commission may recommend that the public utility join with the subdivider in the installation of the sewer system.
('88 Code, § 10-13-6) (Ord. 82-5, passed 4-26-82; Am. Ord. 94-2, passed 4-4-94)
Cross-reference:
Storm drainage and erosion control ordinance adopted by reference, see § 154.02