Two decades ago, state transportation planners were looking ahead when they plotted out a rail-tunnel route about 130 feet beneath Boston. Even though the state couldn’t afford to include the rail tunnel as part of the Big Dig, the designers left a space where they could add one later. The state still doesn’t have money to build the North-South Rail Link, the white whale of New England transportation. But a Boston zoning panel studying land-use rules for the waterfront should show the same kind of foresight as Big Dig planners by recommending protections for the underground route from encroachment. Someday, when the financial and political stars align to build the tunnel, efforts today to keep the route viable will pay off.
There are currently no legal protections for the alignment, but it represents the best available option for someday linking North Station and South Station. That connection, if built, would greatly reduce commuter-rail bottlenecks while also allowing Amtrak passengers to make speedier connections to northern New England. Most of it would run under the Rose Kennedy Greenway, but some would go underneath privately held land.
That’s usually not a problem; tunnel borers routinely burrow under existing structures without incident. But some of the development plans percolating on the waterfront call for huge buildings whose compatibility with a tunnel underneath is less certain. One potential issue is the 30-story tower proposed for the Hook Lobster site next to Fort Point Channel. Buildings that height are currently not allowed, but the Boston Redevelopment Authority’s zoning study is expected to consider relaxing the height limitations, potentially opening the way for a new tower on that site.
Boston shouldn’t fear tall buildings, and the overhaul of the zoning rules is a welcome opportunity to update rules on the waterfront. But one of the new zoning requirements for parcels above the corridor should be a rule that builders present engineering studies showing that the footings of their projects won’t interfere with an eventual rail tunnel. Funding for the rail project may still be far off, but for an inconsequential price now the city can help ensure that the route will still be useable in the future.