MD 4 sign
Motorists Can Expect a Flagging Operation During the Lane Closure
(March 5, 2025) - The Maryland Department of Transportation State Highway Administration will conduct a routine inspection on the MD 4 (Governor Thomas Johnson Bridge) at the Calvert and St. Mary’s County line. The inspection will occur between 6 a.m. and 2 p.m. Sunday, March 9, weather permitting.
One of the bridge’s two lanes will be closed and a flagging operation will be in place. Portable variable message signs will be placed along area state routes to make travelers aware of the closure. Drivers should plan extra time traveling on MD 4 at the Thomas Johnson Bridge.
Customers who have questions about this work may contact the District 5 Office at 410-841-1000 or toll-free at 1-800-331-5603.
Motorists in need may dial #77 on their mobile devices for roadside assistance.
For a list of all major State Highway Administration projects, go to
Project Portal, or visit the homepage at
roads.maryland.gov. For a look at real-time traffic conditions, go to md511.maryland.gov.