Baltimore County, MD Environmental Rules: Erosion Control (2026)

Section 33-5-105(b) prohibits changing the natural ground level of any lot in a way that changes the direction, volume, distribution, or velocity of surface water flowing onto adjoining property without a valid grading permit. Section 33-5-201 requires that grading permit for all land-disturbing activities not otherwise exempt, with narrow carve-outs for individual residential lots covered by a standard erosion and sediment control plan, agency stockpiling yards, and county-run sanitary landfills. Cut-and-fill work has hard geometry limits under Section 33-5-105(c): where a lowered grade meets a neighbor's property, the slope cannot exceed one foot vertical to three feet horizontal unless the county approves otherwise, or the owner causing the grading must build a retaining wall entirely on their own land.

A "standard stabilization note" required on every plan under Section 33-5-104(b)(8)(vi)5 sets firm deadlines: perimeter dikes, swales, ditches, and slopes steeper than 3:1 must be stabilized within three calendar days of disturbance, and all other disturbed or graded areas within seven calendar days. Grading units, the maximum contiguous area that can be open at once, are capped at 20 acres under Section 33-5-101(bb). Plans move through concept, site development, and final erosion and sediment control review by the Soil Conservation District under Section 33-5-103, and an approved plan is valid for two years.

Work in the Chesapeake Bay Critical Area triggers extra replanting: cleared forest beyond the permitted limit must be replanted at three times the cleared area.