Lenexa, KS Environmental Rules: Erosion Control (2026)

Section 4-1-N-4 of the Lenexa City Code requires a permit before any land disturbance activity, and the definition covers tilling, clearing, grading, excavating, stripping, stockpiling and filling, plus covering ground with an impermeable material. Installing sanitary sewers counts. When a building permit is already required, the erosion plan rides along with it under Section 4-1-N-5; when it is not, the owner gets a separate land disturbance permit from the Community Development Director.

Five things are exempt on their own: jobs under 100 cubic yards or under 5,000 square feet, crop farming in the AG District, home landscaping or gardening, reestablishing residential lawns, and emergency work to protect life, property or natural resources. If the work is part of a building project, the building permit is still required.

The application package in Section 4-1-N-7 has a vicinity map and site map, an erosion and sediment control plan, a work schedule, the permit fee, a performance guaranty and, when the City asks, an engineering soils report. The plan must be prepared and certified by a Professional Engineer, a Landscape Architect or a Certified Professional in Erosion and Sediment Control. Disturbing one acre or more also triggers the state and federal construction stormwater requirements, including a KDHE Stormwater Pollution Prevention Plan kept on site. The Director acts within ten business days after receiving every required submission (Section 4-1-N-13).

Section 4-1-N-12 sets the field standards. Cut and fill slopes cannot be steeper than 3:1 without Director approval, and exposed slopes of 4:1 or steeper need silt fence or wattles. Disturbed soil must be stabilized after 14 calendar days of inactivity, or 48 hours when the Director finds high erosivity. Seeding has to germinate within two weeks. Sediment basins are required for drainage areas over 5 acres, sediment traps below 5 acres, and sites over 25 acres must be phased. The permittee notifies the City 48 hours before starting work (Section 4-1-N-19).