LEONARDTOWN, MD — St. Mary’s County Department of Public Works and Transportation will begin roadway improvements on Mattapany Road on or about September 29, 2025. The work, extending from Maryland Route 5 at Point Lookout Road just past St. Mary’s College of Maryland, involves widening the road and applying fresh asphalt paving. Officials estimate completion within 30 days, barring weather delays.
Single-lane closures will occur throughout the project, managed through a traffic control plan with signage and message boards. Drivers should watch for construction equipment and crews, and consider alternate routes such as Route 5 or local side roads to minimize delays. The effort aims to enhance safety and capacity on this key corridor, which sees daily traffic from commuters and college visitors.
Contact Donald Bean at the department at 301-475-4200, extension 3531, for details.
Procedures for such upgrades follow Maryland Department of Transportation State Highway Administration guidelines, which prioritize phased construction to limit disruptions. Crews typically start with milling the existing surface to a depth of 2 to 3 inches, removing deteriorated asphalt before laying a new base layer of hot-mix aggregate up to 4 inches thick. Compaction ensures a smooth, durable finish rated for 15 to 20 years under moderate traffic. Safety measures include flaggers directing one-way traffic during closures, temporary barriers around work zones, and speed reductions to 25 mph, aligning with the road’s existing 30 mph limit east of Route 5.
Environmental considerations play a key role, given the road’s proximity to wetlands and the St. Mary’s River watershed. Permits from the Maryland Department of the Environment require erosion controls like silt fences and sediment basins to protect local streams from runoff, a standard in Southern Maryland projects near sensitive areas.
As work progresses into late October, the upgraded surface will support emergency access and tourism to sites like Historic St. Mary’s City, drawing 50,000 visitors annually. This blend of preservation and progress defines Southern Maryland’s approach, ensuring historic paths like Mattapany serve future generations without losing their foundational role.