Environmental Rules in Gaithersburg, MD (2026)
4 verified environmental rules for Gaithersburg, Maryland, sourced directly from the municipal code and official government pages.
Verified from official government sources
Stormwater Management
Gaithersburg requires city-approved stormwater management for nearly all new development and redevelopment inside city limits under City Code Chapter 8, Article III. Projects disturbing more than 5,000 square feet must control runoff using environmental site design, and the city, not Montgomery County, reviews and permits the plans.
Gaithersburg Stormwater Management Rules
Some RestrictionsGaithersburg City Code §§ 8-19, 8-20
(a)No person shall develop any land for residential, commercial, industrial or institutional uses without having provided for appropriate approved stormwater management measures that control or manage runoff from such developments, except as provided within this section. Stormwater management shall be provided when a site is developed or redeveloped. ... Developments and/or redevelopments that ...
Erosion Control
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.
Gaithersburg Grading and Drainage Requirements
Heavy RestrictionsCity of Gaithersburg Public Works Department – Engineering Services & Environmental Services Divisions
The Public Works Department performs a variety of services including snow removal, street sweeping, repair and maintenance of streets, sidewalks and storm drains, and beautification of streets, public buildings, and parks. Recycling, city vehicle maintenance and stormwater management are also provided. Engineering functions include reviews of site plans, sediment control, storm drainage, paving...
Flood Zones
Gaithersburg bars any grading, filling, new construction, substantial improvement, or watercourse alteration inside a mapped special flood hazard area until a site development permit is issued under Chapter 10. The city's own floodplain administrator, not Montgomery County, reviews every application against the 2006 flood insurance study and FIRM panels for the city.
Gaithersburg Floodplain Development Permit Rules
Some RestrictionsGaithersburg City Code § 10-14(a)
It shall be unlawful for any person to begin any development or construction which is wholly within, partially within, or in contact with any flood hazard area established in section 10-5, including but not limited to: filling; grading; construction of new structures; the substantial improvement of buildings or structures, repetitive loss structures, including repair of substantial damage; plac...
Flood Elevation Requirements
New and substantially improved homes in a Gaithersburg special flood hazard area must have their lowest floor at least one foot above the base flood elevation shown on the city's FIRM. Nonresidential buildings that floodproof instead must reach two feet above BFE, the city's defined 'flood protection elevation.'
Gaithersburg Base Flood Elevation Freeboard Rule
Some RestrictionsGaithersburg City Code § 10-34(a)
(a)Elevation requirements.(1)Lowest floors shall be elevated at least one foot above the established base flood elevation.(2)In areas of shallow flooding (zone AO), the lowest floor (including basement) shall be elevated at least as high above the highest adjacent grade as the depth number specified in feet on the FIRM plus two (2) feet, or at least four (4) feet if a depth number is not specif...
Looking for Montgomery County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Gaithersburg city rules.
Environmental Rules in Montgomery County →