The following shall be the minimum specifications for the construction of street access and storm water drainage facilities:
(A) Materials for all items of construction of any description or nature shall conform to standards set out in Kentucky D.O.T. specifications, except as herein set out or described. In cases of dispute arising relative to construction method or materials, the Kentucky Standards for Road & Bridge Construction 1994, or the most recent edition, shall govern.
(B) All drains, catch basins, concrete driveway entrance culverts, ditches, swales or any other means of storm water conveyance shall be sized so as not to impede the flow of storm water. The applicant is responsible for determining pre-construction and post-construction flows for all affected drainage facilities. In no case shall post-construction flow exceed the pre-construction flow. Applicants shall submit all appropriate calculations used to verify design.
(C) Calculations shall be based on a twenty-five (25) year return interval, except that no culvert shall be less than fifteen inches (15") in diameter without written consent of the city. Consent may only be granted where calculations conclude a small size will carry the storm water at the location proposed and that a smaller culvert will not create cleaning and maintenance problems.
(D) Where existing drainage facilities, bridges, culverts, trench drains or swales have to be replaced due to failure, danger of failure, or simply wear and tear, they shall be sized and installed according to this subchapter regardless of whether publicly or privately owned and maintained.
(E) No road, drainage ditch, or swale along a public road or on public land may be filled in or altered without a written permit. When culverts are allowed to replace or supplement drainage ditches or swales, sizing of the culverts shall be based on the twenty-five (25) year return interval. Access for cleaning and catch basins shall be required and shall not be spaced in excess of forty (40) foot intervals without written permits. All catch basins shall have an inside horizontal cross measurement at least as large as the diameter of the pipe.
(F) No swale or road drainage ditch shall be filled so that minimum surface flow is above the bottom of the street bedding (minimum 10" below street surface) except with written permission from the city.
(G) Water from parking lots shall not drain onto public streets unless such streets contain a storm water system or curb and gutters capable of carrying away such storm water without allowing the storm water to flow into the traffic carrying areas of the street (no more than two feet (2') into the street from back side of curb). Where storm sewers and drainage ditches are available, trench drains or concrete-paved swales shall be installed at the property line to direct all surface water into the storm sewer or drainage ditches. In no case shall storm water be allowed to enter upon a street or road where it creates puddles, standing water, or where it causes ice to form on the street.
(H) It shall be unlawful for any person to place any fill, dirt, debris, trash, brush, trees or stumps or any other items or materials into any stream that will obstruct, impede, or divert the flow of water or affect the water-carrying capacity of a storm or drainage ditch.
(I) Culverts placed in drainage ditches adjacent to a road or street for a driveway or road intersection shall be a maximum of forty feet (40') in length.
(Ord. 24:95, passed 9-11-95; Am. Ord. 18:97, passed 8-11-97)