Baltimore faces an increasing threat of coastal flooding from rising sea levels, worsened by storms like Debby. To help manage that risk, the U.S. Army of Corps Engineers announced this week it would recommend Congress fund about $77 million to build floodwalls to protect two of the city’s major thoroughfares, the Fort McHenry and Harbor tunnels.

The plan comes after USACE and the Maryland Department of Transportation completed a three-year study into coastal flooding problems around Baltimore and potential solutions. They found that about 9,500 feet of fixed floodwalls should be installed along the southern approach to the I-95 Fort McHenry Tunnel and I-895 Harbor Tunnel entrances and around nearby ventilation buildings.

“The people of Baltimore know all too well the impact caused when vital transportation infrastructure is lost,” Lt. Gen. Scott A. Spellmon, the commanding general of the Army Corps, said in a release on Monday. “This project would improve the resiliency of the tunnels, which are critical routes for the transportation of goods and services in the state of Maryland and along the Eastern seaboard.”

Spellmon signed off on a chief’s report underwriting the findings last week. The study and funding recommendation come as the collapse of the Francis Scott Key Bridge in March means motorists are using the tunnels as alternate routes more than ever.

The Fort McHenry Tunnel is used by approximately 45 million vehicles per year and the Baltimore Harbor Tunnel sees nearly 27 million vehicles per year, according to Joe Bieberich, the project manager for the storm risk study.

“It is very important to make sure these critical transportation routes remain open during a coastal storm event, maintaining access to jobs, commercial transportation routes and emergency services,” Bieberich said in the release.

The Army Corps and Maryland Transportation Authority are set to begin design work on the floodwalls later this year. Construction is expected to start in 2027, pending congressional authorization and funding.