MD 190 Stream Restoration and Culvert Replacement. Potomac, Maryland.

A crushed and dual-cell culvert and a downstream, undersized culvert at a driveway caused frequent overtopping of a busy section of MD 190 in Potomac, MD. Whitman, Requardt & Associates, LLP (WRA) analyzed hydrologic/hydraulic conditions and designed a dual-cell 76” x 48” HERCP replacement that allowed for widening of MD 190. Design included removal of restrictive downstream culvert, channel re-grading using adverse slopes, removal of invasive plant species (bamboo) and replacement with live-stake bank stabilization. Upstream grade-control step pools were integrated into the effective hydraulic design reach. A sand filter stormwater management BMP was also designed. The project included construction staging, maintenance of stream flow design, structural design, foundation analysis and recommendations, roadway design, H&H evaluation and scour countermeasure design, erosion and sediment control, MOT plans, utility relocation coordination, and permits/approvals.