Grading & Drainage: Gaithersburg vs Rockville
How do grading & drainage rules compare between Gaithersburg, MD and Rockville, MD?
Gaithersburg and Rockville have similar restriction levels.
Gaithersburg, MD
Montgomery County
Gaithersburg requires grading permits for land-disturbing activities and enforces drainage standards to protect adjacent properties and waterways. Grading must maintain positive drainage away from structures and must not redirect stormwater onto neighboring properties. Montgomery County reviews grading plans in coordination with the city for projects meeting disturbance thresholds.
View full Gaithersburg rules →Rockville, MD
Montgomery County
Rockville requires grading permits and drainage plans for projects that disturb 5,000 square feet or more under Chapter 19 of the City Code. Finished grading must provide positive drainage away from all building foundations. Standing water on lawns must drain within 24 hours after rainfall, and drainage may not be redirected onto adjacent properties.
View full Rockville rules →Key Facts Comparison
| Fact | Gaithersburg | Rockville |
|---|---|---|
| Grading Permit | Required for drainage changes | - |
| Foundation Slope | 6 inches in first 10 feet | - |
| Retaining Wall Permit | Over 4 feet height | - |
| Public Works | (301) 258-6370 | - |
| Building Division | (301) 258-6330 | - |
| Code Reference | - | Chapter 19, Rockville City Code |
| Permit Threshold | - | 5,000 sq ft or 100 cu yd |
| Drainage Standard | - | 24 hours to drain lawns |
| Max Slope | - | 3:1 in lawn areas |
| Contact | - | 240-314-8567 |
Highlighted rows indicate differences between cities.
Gaithersburg FAQ
Do I need a grading permit in Gaithersburg?
A grading permit is required for land disturbances that change drainage patterns, involve significant cut or fill, or meet the 5,000-square-foot disturbance threshold. Contact the Building Division at (301) 258-6330.
Can my neighbor's grading cause water to flow onto my property?
No. Grading must not redirect stormwater onto neighboring properties. If a neighbor's work has changed drainage patterns affecting your property, contact Public Works at (301) 258-6370 to file a complaint.
What slope is required around foundations?
Finished grade must slope at least 6 inches downward in the first 10 feet from the foundation to ensure positive drainage away from the structure.
Rockville FAQ
When do I need a grading permit in Rockville?
A grading permit is required when your project disturbs 5,000 square feet or more of land or moves 100 cubic yards or more of soil. Contact the Department of Public Works at 240-314-8567.
Can I redirect drainage onto my neighbor's property?
No. Grading must not redirect surface drainage onto adjacent properties without appropriate easements. Violations may result in code enforcement action and civil liability.
How quickly must my yard drain after rain?
Finished grading must allow lawns to drain within 24 hours after rainfall ends. Designated drainage courses may take up to 48 hours.
Compare other topics
See how Gaithersburg and Rockville compare on other ordinance categories.
Want to add a third city?
Use our full comparison tool to compare up to three cities.
Open Comparison Tool