No discussion of the threat posed to Boston by rising sea levels would be complete without a mention of the 1988 proposal by Boston urban planner Antonio DiMambro to protect the city with a flood-control structure from Deer Island to Long Island. This week's Boston Harbor Association's conference on the rising sea level did not disappoint.
Amid talk of other adaptation measures, from flood-proofing buildings to using pumps and retention ponds at Logan, those in attendance also learned about DiMambro's plan to shield the inner harbor and downtown from wicked high tides and storm surges. Under his proposal, the structure would allow navigation and normal tide flow through gates.
The challenge is dealing with normal tides that are 2.5 feet to 5 feet higher than now, plus 100-year storm surges of another 5 feet. Scientists and policy-makers at the conference were careful to emphasize that the country should take all possible steps to slow climate change by reducing greenhouse gas emissions, but that government and the private sector will also have to take steps to adapt to the effects of climate change. One Princeton architecture professor described "soft infrastructure" proposals to protect New York harbor with small artificial islands and barrier reefs that would dissipate the energy of storm surges.
Conference speakers displayed maps showing floods in virtually every part of the city that has been filled in since it was marshland, from Logan runways to the Back Bay and South End (this is a baseline map of Boston, and here are maps showing the results if sea levels rise increasingly dire scenarios).
One adaptive measure that architects of Partners HealthCare's new Spaulding Rehabilitation Hospital learned from Katrina: The windows of the facility in Charlestown will be key-operable so that, if an emergency knocks out air-conditioning, hospital staff can at least open the windows without smashing them, as happened in New Orleans.
The greater lesson from Katrina is that man-made flood-control structures often fail to do the job, but that did not stop participants from talking about the DiMambro plan. Maybe it's time to bring in the Dutch instead.