MD 4 sign

MD 4 sign

​$283 Million Project Will Improve Traffic Flow, Safety Along Corridor 

(May 2, 2024) –The Maryland Department of Transportation State Highway Administration is beginning work on a $283 million project to improve safety and mobility at the intersection of MD 4 (Pennsylvania Avenue) and MD 337 (Suitland Parkway) in the Upper Marlboro area of Prince George’s County. 

The project, which will provide enhanced traffic operations throughout the corridor with the construction of a new diamond interchange, is expected to be complete in 2028, weather permitting.

map of MD 4 and MD337 interchange
Map of MD 4 and MD 337 interchange

In addition to the new diamond interchange, the project includes:

  • realigning the Pennsylvania Avenue Service Road and Armstrong Lane,
  • reconstructing on- and off-ramps to Joint Base Andrews,
  • constructing a new signalized intersection at Presidential Parkway and Central Park Drive, along with new sidewalks,
  • constructing a new two-lane ramp over MD 4 to provide a direct connection between northbound MD 4 and westbound Suitland Parkway,
  • adding a new shared-use path across the Suitland Parkway bridge,
  • constructing four new bridges,
  • realigning Presidential Parkway with Suitland Parkway, and
  • realigning and widening MD 4. 

“The new interchange at MD 4 and Suitland Parkway is critical for residents and commuters, and will accommodate economic growth throughout the region,” said Maryland Transportation Secretary Paul J. Wiedefeld. “The project will improve mobility and accessibility, and advances our mission to deliver a comprehensive, world-class transportation system for all.”

Rendering of the future MD 4 and MD 337 (Suitland Parkway) interchange.

Rendering of the future MD 4 and MD 337 (Suitland Parkway) interchange.

The MD 4 and MD 337 interchange will improve safety and provide capacity along the corridor to accommodate growth in the surrounding areas. MD 4 is a major route for commuters heading west to Washington, D.C., east to Upper Marlboro and southwest to Joint Base Andrews. The corridor carries average daily traffic of 66,000 vehicles and experiences congestion during peak hours. The project will ease congestion and meet the current and future travel demand.

“Our team is excited to be underway on this critical project,” said State Highway Administrator Will Pines. “We appreciate the cooperation and partnership with local residents, community groups and stakeholders. Once completed, these improvements will serve Prince George’s County and the surrounding area for generations.”

In recent months, crews initiated preliminary work including utility relocations and tree clearing near the project site. During construction, temporary single- or double-lane closures may be in effect 24/7 on MD 4. Additional lane closures may be needed to expedite the work and keep the project on schedule. Concrete General Inc., of Gaithersburg, will perform the work. 

As work areas shift during various project stages, the State Highway Administration will keep residents informed through mailers, social media and on the Project Portal page here​. Customers with questions may contact the District 3 Office at 301-513-7300 or toll-free at 1-800-749-0737.

The State Highway Administration appreciates customers’ patience during construction as we work to improve Maryland’s transportation system. Drivers are asked to stay alert, stay focused and be aware of reduced speed limits and changing driving patterns in the work zone. Slow down and move over in work zones. It’s the law. 

​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 roa​ds.maryland.​gov. For a look at real-time traffic conditions, go to md511.mary​