Advertisement Boston 'wiped out as a city' if Harvey hit, Walsh says Share Shares Copy Link Copy

While Boston sends help to Houston as that city recovers from record rainfall and devastating flooding, Boston Mayor Martin Walsh is turning his attention to how Boston would cope with a similar storm. What he knows so far: every option is an expensive one.During an appearance on Boston Herald Radio on Wednesday morning, Walsh said the impacts of Harvey are "forcing us to sit down at a table with my team and talk about what we would do in a case like this," but the mayor acknowledged that such a storm would decimate the city."If we got hit with a storm like this, if Harvey hit Boston Harbor, we're wiped out as a city," Walsh said. "We can't prevent it today. What we can do is evacuate, make sure people get out of their homes, make sure that we have contingency plans for people that get out of their homes, make sure that we have plans for rebuilding, making sure we don't have the looting that's going on in Houston right now and clamp down on public safety in the community, but that's all we could do right now. Really, seriously, when you think about it."Walsh specifically mentioned a proposal that has been floated to build a massive barrier in Boston Harbor that could control the flow of water into the inner harbor. The Boston Globe wrote about the idea in February and reported that the idea "is now under serious study by a team of some of the region's top scientists and engineers, who recently received a major grant to pursue their research.""There was a story somewhere that talked about we could build a $10 billion basically dam in Boston Harbor but it would cost $10 billion. That's crazy," Walsh said. "If we got hit with Harvey, we're probably talking $50-60 billion worth of damage. Does that $10 billion figure look that crazy anymore?"The mayor stressed that he does not know if the dam is a "real potential" and said, "We don't have, obviously, $10 billion," but added that the city must begin to think about this sort of thing."We have to start thinking more and more about this stuff," he said. "We have to start looking at the city, where, in fact, would we evacuate to? Would we have to evacuate the entire city?"The city's Green Ribbon Commission has already begun researching what climate change and sea level rise would mean for Boston. The commission reported this year that without improvements to the city's stormwater drainage system more than "11,000 structures and 85,000 people will be directly exposed to frequent stormwater flooding" as early as the 2070s."As sea levels continue to rise, severely damaging floods will shift from a rare occurrence to a monthly reality. In the near term, a flood event inundating 5 percent of the city will have a 1 percent chance of occurring in any given year," the commission's report states. "By midcentury, such a flood will become ten times more likely, and by the late century, that magnitude of flooding will occur at least once a month. This means that between 10 percent and 20 percent of Charlestown, East Boston, Downtown, and South Boston will face hightide flooding, even when there is no storm."No matter what Boston ultimately does to deal with rising seas and the potential for more powerful storms, Walsh said, it will not come cheap."Whatever the answer is, in Boston or anywhere in America on the coast, it's expensive," Walsh, the former head of the Boston Building Trades, said. "It's going to be an expensive project, whatever we do."Rep. Byron Rushing, who represents parts of the South End and Back Bay, tweeted Tuesday evening that he agrees with Walsh that Boston needs a plan "sooner (rather) than later" and offered constituents a way to discern whether their property might be susceptible to flooding."Ignore the consultants-Want to know if you're prone to flooding, get an 1815 map of Boston, your streets not there? Buy an inflatable boat," he tweeted.