MD 4 sign
Nighttime Flagging Operations Begin at 9 p.m. Sunday Night, January 18
(January 13, 2026)- The Maryland Department of Transportation State Highway Administration will begin routine structural and maintenance work on the MD 4 Bridge over the Patuxent River (Governor Thomas Johnson Bridge) at the Calvert/St. Mary’s County line beginning Sunday, January 18. The nighttime work will continue through late February, weather permitting.
Crews will close a single-lane and alternate traffic in the open lane using an overnight flagging operation Sunday through Thursday, 10 p.m. until 5 a.m. the following morning. This work includes bridge joint seal replacement, metal welding and other repairs.
Portable variable message signs will be placed to make travelers aware of the lane closure. Work will be performed by contractor Covington Machine and Welding of Annapolis.
Overnight travelers should plan extra travel time to cross the bridge. This work is necessary to ensure a safe and reliable transportation system. Drivers are asked to stay alert, stay focused, look for reduced speed limits as well as driving pattern changes, and slow down in construction zones.
The State Highway Administration is Serious About Safety. Pedestrians and motorists are urged to remain alert and avoid distractions when traveling through the work zone. Motorists should obey all posted speed limits.
Motorists can dial #77 on their mobile devices for roadside assistance.
For a list of all major State Highway Administration projects, news and travel information, visit roads.maryland.gov.