D.C. health officials will test the water quality of the Potomac and Anacostia rivers daily, after a recreational advisory for the Potomac triggered by January’s historic sewage spill was lifted this week.
Hundreds of millions of gallons of untreated wastewater flowed into the Potomac after a portion of the Potomac Interceptor in Montgomery County, Maryland, failed.
“We usually do weekly testing,” Director of D.C. Health Dr. Ayanna Bennett said. “We’re pretty confident about the testing we’ve had. We just want to be really observant as we move forward.”
Crews from the city are independently testing the water at a half dozen sites along the Potomac and Anacostia rivers, including Fletcher’s Cove, the Key Bridge and the Anacostia Park boat ramp.
They toss a bucket out into the middle of the river to take a sample, which is bottled, put it on ice and sent to an independent Environmental Protection Agency lab at Fort Meade in Maryland.
At the lab, they count how many E. coli bacteria are in that sample. Bennett said results return in around two days.
“We are back to our usual conditions, at least in terms of the bacteria levels that we’re seeing,” Bennett said.
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“We want it to be 410, or below. It does wax and wane, so it is usually under that level the majority of the time,” Bennett said.
Officials in D.C., independent of D.C. Water, will continue to monitor how the water changes as it gets warmer, and the region sees more rain that taxes the stormwater and sewer systems in the city.
After the Potomac Interceptor collapsed Jan. 19, approximately 240 million gallons of sewage flowed from the C&O Canal National Historical Park into the Potomac. Though it is considered the worst sewage spill in American history, Bennett said the river is doing its job.
“There was never a sense that this sewage spill was going to sit there, because it didn’t fall in a stagnant piece of water. It fell in an active, really flowing river. And it’s done what we expected it to do,” Bennett said.
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