Credit: Photograph by Darrow Montgomery

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Three times in the span of two weeks in July, heavy rain brought damaging floods to the Bloomingdale neighborhood in Northwest, with some homes getting invaded by raw sewage. Mayor Vince Gray formed a task force to study the issue and pledged short-term fixes by year’s end. But that wasn’t fast enough for Bloomingdale: In September, flooding struck again, leaving one man on Rhode Island Avenue at the mercy of rescuers after rising water trapped him in his car and prompting Ward 5 Councilmember Kenyan McDuffie to call for a relief fund for victims.

So Bloomingdale residents were understandably on edge as Hurricane Sandy approached in late October. And yet…not much happened. As the storm ravaged the eastern seaboard, there wasn’t even any street flooding in Bloomingdale. The reason was simple mathematics: The sewers can handle lots of rain, as long as it doesn’t come down too fast. Sandy dropped about four inches of rain on the city, but over the course of more than a day, compared to the three inches that the September storm deposited in just two hours.

The city’s long-term solution to the flooding problem won’t arrive for more than a decade, but in the meantime, DC Water broke ground in early December on a project to use a portion of the McMillan Sand Filtration site to divert stormwater. That could be finished by 2014. In the meantime, let’s hope for no heavy storms—or at least slow ones.