The United States Army Corps of Engineers (USACE) and the City of Boston have partnered to build flood protection along the city’s extensive 47-mile coastline. The USACE proposes a 16-mile network of levees, floodwalls, and elevated greenspaces across South Boston, East Boston, Dorchester, Charlestown, and the North End to protect Boston into the next century.

The City’s draft Coastal Storm Risk Management Feasibility Study reports that 40% of residents live in areas at risk of coastal flooding. Without upgrading key coastal areas, USACE estimates that residents, businesses, and the public sector could face $54 billion in flood-related losses by 2090. The project will not be cheap, with estimates around $10 billion for basic improvements alone, but USACE predicts that the draft plan will save $4 for every $1 spent.

“The reality is that doing nothing is not a viable option,” said New England District USACE Deputy Commander David MacPhail. “Without action, the costs to public safety and economic vitality from coastal flooding will only be compounded.”

Mayor Michelle Wu called the project the largest investment in Boston’s waterfront, doubling the Boston Harbor Clean-up. Through a partnership with USACE, the project can also benefit from federal funds covering up to 65% of the costs to construct climate-resilient infrastructure. State, private, and philanthropic funds will also be pursued.

South Boston’s Fan Pier could see a 6-foot floodwall integrated into the community by raising the existing Harborwalk atop the structure.

Raymond L. Flynn Marine Park has a drafted plan to build a 6-foot floodwall built into the marine park by elevating the existing grounds and constructing floodgates to allow vehicular access to its docks, wharves, and piers. USACE also proposes omitting the facility entirely from flood protection.

Dorchester could see raised levees along Pattens Cove and Pope John Paul II Park. Elevated Harborwalks built at these locations would also offer the public access to views of the waterfront. At Tenean Beach, the USACE proposes constructing a levee and gradually raising Conley Street by 6 feet and sloping down to meet the existing grade at the I-93 overpass, maintaining vehicular access clearances.

In East Boston, an integrated floodwall is proposed for LoPresti Park. The MBTA Blue Line tracks behind Constitution Beach would also require a floodwall that connects to levees along Bayswater Street. The beach and park itself would be preserved unaltered.

The USACE draft shows two options for protecting the Route 1A corridor. The USACE prefers to build a 6-foot floodwall with the median along Route 1A, requiring the southbound traffic lanes to close during a storm and moving the pedestrian crossing to a new location, the officials from The City said.

Boston’s preferred option would be to construct 3- to 9-foot floodwalls along the waterfront of Chelsea Creek, integrating the structure with a new Harborwalk.

New floodwalls and floodgates would also be built between Maverick Street and Boston Logan International Airport.  The gate would stay open outside of severe weather to ensure access to the Harborwalk. Tomahawk Drive would be raised 6 feet to connect floodwalls and provide continuous protection.
In Charlestown, USACE proposes floodwalls along the Navy Yard and Little Mystic Channel, ranging from approximately 6 to 9 feet high. A 30-ft-wide floodgate integrated into the 13th Street (Pier 8) Opening could be closed to prevent flooding during storms.

Councilor Gabriela Coletta Zapata, whose district represents some of Boston’s most climate-vulnerable neighborhoods, said she is grateful for the once-in-a-generation opportunity to invest in infrastructure that will be able to withstand the impact of climate change.

“The release of the [USACE] Draft Coastal Storm Risk Management Feasibility Study is a critical milestone that brings us closer to making the transformative investments needed to protect our residents, neighborhoods, and critical infrastructure from the growing threats of sea level rise and coastal storms,” she said. “This achievement reflects years of collaboration among government, community organizations, the private sector, and residents, all working toward a resilient waterfront that will protect Boston for generations to come” 

The full 600-page study will be released Friday, July 24. It will then enter a public comment period until September 18, at 5 p.m. The designs currently listed in the report are not final and are meant to serve more as concepts on how the USACE could impact the community.

Feedback can be shared virtually, via e-mail, or in writing. A “How-to Guide” and public comment worksheet are now available.