Gaithersburg, MD Environmental Rules: Erosion Control (2026)

Gaithersburg enforces erosion and sediment control requirements under Maryland Environment Article Title 4, Subtitle 1 and Montgomery County Code Chapter 19. Any land-disturbing activity that affects 5,000 square feet or more of land area or involves movement of 100 cubic yards or more of earth requires an approved erosion and sediment control plan before a grading permit is issued. Plans must be prepared in accordance with the Maryland Standards and Specifications for Soil Erosion and Sediment Control, published by the Maryland Department of the Environment (MDE). Montgomery County Department of Permitting Services reviews and approves plans and conducts inspections during construction. Required practices include silt fences, sediment traps, stabilized construction entrances, dust control, temporary and permanent seeding, and inlet protection for storm drains. Disturbed areas must be stabilized within 14 days of final grading or 7 days during the wet season (October through March). Responsible personnel must inspect erosion controls within 24 hours of any rainfall event of 0.5 inches or more. Even smaller residential projects like grading for patios, driveways, or landscaping may require controls if they meet the disturbance threshold. Contact Montgomery County DPS at (240) 777-6370 for grading permit and erosion plan requirements.