Washington County, MD Fence Regulations: Retaining Walls (2026)

14 of the county's Stormwater Management, Grading, Soil Erosion and Sediment Control Ordinance, use of a retaining wall tied to any land-disturbing activity must be shown on the grading plan submitted with the grading permit application to the Division of Plan Review and Permitting. Any proposed wall over three feet high cannot rely on a stock design: it must be designed according to the applicable Building Code and/or the AASHTO (American Association of State Highway and Transportation Officials) standard, meaning a qualified design professional's engineering is required once the three-foot threshold is crossed.

The same ordinance carries this requirement into the grading plan submittal itself. l, covering Standard Grading Plan requirements, requires that existing and proposed retaining walls be shown with top-of-wall and bottom-of-wall elevations, and for any proposed wall over three feet in height, the plan must include a wall profile and detail section meeting the requirements of the Division of Plan Review and Permitting. B allows the Division to require an engineering analysis by a Qualified Professional wherever a design proposes ponding of water above a retaining wall, to verify stability.

D likewise lets the Division and the Soil Conservation District increase minimum setbacks near slopes and walls based on a Qualified Professional's recommendation if needed for stability or to prevent damage from surface water, soil, or debris. Because the retaining-wall rule sits inside the grading and stormwater ordinance rather than the zoning ordinance, it applies whenever a wall is built as part of a land-disturbing activity requiring a grading permit, county-wide outside the limits of Hagerstown, Boonsboro, Williamsport, Smithsburg, Funkstown, and Hancock, which administer their own codes within town limits.