MD 450 sign

MD 450 sign

(October 27, 2020) – The Maryland Department of Transportation State Highway Administration (MDOT SHA) has completed a $1 million drainage and maintenance project on MD 450 (Defense Highway) in Anne Arundel County. These improvements will protect roadway integrity and manage water flow along the route between the Gambrills and Davidsonville communities.     

“We worked very closely with members of the community to deliver this essential project that will reduce the impact and duration of road closures after precipitation,” said MDOT SHA Administrator Tim Smith. “We have already seen great improvement as demonstrated when waters receded and MD 450 reopened the same day we experienced Tropical Storm Isaias.”   

Crews from MDOT SHA’s contractor on the project, AJ Romano Construction Inc. of Laurel, addressed deteriorating structural conditions in the watershed by replacing culverts and removing sediment. Additional landscaping was installed to further stabilize the stream channel. Learn more about the project HERE.     

In 1954, MD 450 was built atop a stream bed in the Bell Branch/North River stream valley. The watershed discharges into the South River and is approximately 21 square miles long. Over the years, growth in the area reduced the number of trees and increased the amount of water-resistant surfaces, resulting in more stormwater runoff in the watershed. Due to its location within this marshy area, the stretch of MD 450 between Rutland Road and Huntwood Drive has been susceptible to tidal and non-tidal flooding even on sunny days.   

“The MD 450 project improves stormwater management and will result in more reliable access for residents and commuters,” said MDOT Secretary Greg Slater. “We’re excited to complete this restoration with the help and support of our partners in the community and county government.”   

MDOT SHA crews will continue routine maintenance operations now that this project is completed.  Motorists should note that even with these improvements, severe weather events can still result in standing water. Flood area and travel advisory signs are in place.
The MD 450 project is another example of work accomplished by MDOT SHA during Maryland’s COVID-19 emergency. Crews and contractors have continued to work while following state and federal health and safety guidelines.

MDOT SHA works to maintain safe traffic mobility in work zones for our crews and our customers. Drivers need to stay alert, focus on driving and, look for reduced speed limits, as well as other driving pattern changes.

For a list of all major MDOT SHA projects, go to Project Portal. Visit our homepage at For a look at real-time traffic conditions, go to

Editor’s Note

From intersection improvements to widening and new interchange construction, MDOT SHA is investing in projects to enhance the commute and daily travel for millions of Marylanders.  MDOT SHA maintains more than 2,500 bridges and 17,000 miles of non-toll state roads – the interstate, US and state numbered routes in Maryland’s 23 counties.