Midland County, TX Environmental Rules: Stormwater Management (2026)

1, Surface Grading, sets the basic drainage duty for every platted lot: lots and private property shall be graded so that surface drainage is taken to streets or drainage courses as directly as possible, and drainage water from roads and streets must likewise be routed to defined drainage courses as directly as possible. 4, Permanent Drainage Structures, which requires that culverts, pipes, drainage boxes, and bridges be installed at every crossing of a drainage flow path identified in the county's Drainage Manual, whether the crossing is a ditch, a driveway, a road, or a street, and that those structures conform to standard and accepted engineering practices.

6 adds a construction spec for the roughest crossings: low-water crossings and roadways crossing streams need reinforced embankments built with concrete tested to 3,000 pounds per square inch, specifically to prevent erosion of the embankment. 5 requires an engineer to fix the exact dimensions and type of every permanent drainage structure before Commissioners Court grants or denies preliminary plat authorization. 8, which requires a drainage study specific to the site's watershed for every proposed development and, where FEMA has mapped a Zone A flood hazard without elevation data, requires base flood elevation data for subdivisions over fifty lots or five acres.