Shadow rules in Copley too stiff a price for tower

The now-closed Winthrop Square garage.
The now-closed Winthrop Square garage. DAVID L. RYAN/GLOBE STAFF/FILE

Mayor Martin J. Walsh’s plan to sell a city-owned garage to developers, who would construct a 775-foot skyscraper on the site, has stirred concern about the shadows the tower would cast on the Common and the Public Garden.

That concern is misplaced. The shadows would be a minor nuisance, gone by 9:30 a.m. at the latest. The skyscraper, to be built on Winthrop Square, would include badly needed housing in an increasingly unaffordable city. And the sale would provide the city with a rare $153 million cash infusion to be spent improving the Common, Franklin Park, and public housing all over Boston.

The real question isn’t whether there’s too much shadow in this deal — it’s whether there is enough.

The tower, as planned, would violate state laws dating to the 1990s that limit shadows on the Common and the Public Garden. In order to get the project built, Walsh is asking the Legislature to carve out an exemption.


But in exchange, the city would accept new restrictions on shadows elsewhere in the Common and up the road in Copley Square. It’s a compromise — a concession to neighborhood activists pre-occupied with shade.

But before they make that concession, the mayor and state lawmakers — particularly the Boston delegation — should think about whether the city is giving up too much in the way of future development in some of its most important corridors.

Boston’s real estate market is booming and the city’s knowledge-based economy has positioned the region for long-term prosperity. The city needs to plan for that prosperity.

That means seeking maximum flexibility. It means keeping the door open for more projects like Winthrop Square, whose benefits stretch far beyond their morning shadows.

The desire to protect open space — particularly a space as iconic as the Common — is understandable. And some sort of compromise is probably warranted here. Approving tighter limits on shadows elsewhere in the Common in order to get the Winthrop Square tower built seems like a reasonable trade-off.

But concerns about shade shouldn’t play an outsize role. One question all the players should be asking themselves: Does this deal really need to creep all the way to Copley Square?