If Boston is going to avert the most catastrophic impacts of projected sea level rise this century, it needs to get building.

A new landmark draft plan set to be released this week from the US Army Corps of Engineers in partnership with the city recommends 20 specific projects to shore up the most flood-prone parts of Boston.

Some 20,000 buildings and 40 percent of the city — more than a quarter-million residents — at risk of flooding are depending on it.

“Today marks a major milestone in Boston’s fight to protect our city from climate change,” Mayor Michelle Wu said at a press conference along the waterfront in the North End. “This study … will give us the clearest picture we’ve ever had of how rising seas and stronger storms threaten our neighborhoods, and importantly, the report also will lay out a plan for Boston to become the greener, healthier, more resilient city our residents deserve.”

The draft plan is set to act as a roadmap for how New England’s largest city, one-sixth of which is built on filled tidelands, can navigate the more than four feet of sea level rise the Army Corps projects will hit Boston by 2090 as the world continues to warm. It’s also a glimmer of cooperation between the federal government under President Trump and a deep-blue city in a state with a Democratic trifecta in what has otherwise seen a souring relationship.

If all goes to script and the draft plan for Boston — which has an estimated price tag of $10 billion — is finalized in roughly its current form, in the years and decades ahead, new floodwalls up to nine feet high could dot the edges of the harbor in Charlestown, the North End, and South Boston. Levees could be built at Pattens Cove, Tenean Beach, and Pope John Paul II Park in Dorchester. And floodgates could go up right outside Logan Airport in East Boston.

There’s a key sweetener, too: Boston can pass up to 65 percent of the tab on to the federal government for the construction of the infrastructure that the Army Corps recommends to protect the city from flooding.

Delivering the final study to Congress in two years from now — which will mark a six-year process that kicked off in 2022 — is just the first step. Federal lawmakers will need to appropriate money to fund the suite of flood control projects every two years, requiring Boston to continue to make the case and compete with other cities for funding.

The plan comes as Massachusetts is hitting a critical crossroads with respect to the adverse economic consequences of flooding around the state, from rising insurance costs to lost property value for homeowners and businesses. That’s now prompting state officials to consider more sweeping and potentially contentious reforms, including a voluntary buyout program now under discussion and efforts to require property owners to disclose their flood risk and prior flooding history.

More Context

• Climate reckoning: Mass. communities stare down the prospect – and complications – of a retreat from rising waters (March 2026)