Kenton County, KY Environmental Rules: Stormwater Management (2026)

11(A) sets the baseline rule for every entrance built along a Kenton County road: it "shall not obstruct or restrict the normal water drainage along or across the county road, unless suitable provisions are made therefor," and the Public Works Superintendent must be satisfied the proposed drainage features are adequate for present and future needs and have a reasonable life span, including approval of the pipe material itself. Subsection (B) then itemizes ten specific requirements. Entrance pipe cannot tie into existing roadway drainage structures unless junction boxes, manholes and catch basins are installed to county specifications, and the pipe itself must be "not less than 15 inches in diameter and not less than 20 feet in length," per Public Works standards and standard drawings RDB 110-01 or 111-02.

Where long pipe runs are used, catch basins or clean-out boxes go in at roughly 50-foot intervals for 15-inch pipe, and gratings must keep driveway water from flowing over sidewalks or the roadway. Fill placed against an existing road must slope 6:1 down to the ditch or a three-foot depth, with french or toe drains as needed. Any proposal that significantly alters a drainage area requires "a complete drainage survey (upstream and downstream) based on a 25-year and 100-year storm with hydraulic analysis," prepared by a registered, licensed engineer.

12 goes further, making a permittee whose development overloads downstream county drainage facilities responsible for either fixing those facilities or building an on-site retention basin, at the permittee's own risk for resulting damage claims.