Denton, TX Environmental Rules: Grading & Drainage (2026)

Denton regulates grading and drainage through the Denton Development Code and the Denton Drainage Design Criteria Manual. All development projects, including new home construction and significant site improvements, must submit a grading and drainage plan as part of the building permit application. The plan must show existing and proposed contours, drainage flow directions, swale locations, and any proposed connections to the municipal storm sewer system. Finished lot grades must direct surface water away from building foundations and toward approved drainage facilities. A minimum slope of 2 percent is recommended within 10 feet of the building foundation. Grading must not alter drainage patterns in a way that directs additional stormwater onto adjacent properties. A grading permit is required for earth-moving activities that alter existing drainage patterns, import or export more than 50 cubic yards of fill, or change grades by more than 12 inches. The Denton area has expansive clay soils that are prone to swelling and shrinking with moisture changes, making proper grading and drainage critical for foundation stability. Retaining walls over 4 feet in height require engineering design and a separate building permit. All drainage easements must remain clear and unobstructed, and property owners are responsible for maintaining drainage swales and channels on their property.