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The swimming portion of the Nation’s Triathlon was cancelled this week due to a bunch of shit—-and not the metaphorical kind.

D.C.’s old sewage pipes overflowed after Saturday night’s rainstorm, causing a mixture of raw sewage and storm water to overflow into the Potomac River for 15 minutes, according to Collin Burrell, the associate director of water quality at the District Department of the Environment. Officials believed high bacteria levels—-specifically E.coli—-would not be safe for swimmers.

Sewage spills are not uncommon in the Potomac and, because of this, swimming is prohibited in the water except for special events. The Nation’s Triathlon was approved to hold the swimming event. On Thursday, Sept. 4, DDOE sent marathon organizers a letter saying the water was safe for the swimming. But, the letter warned, the weather forecast calls for a storm Saturday, which could spike the bacteria levels in the water. The letter, in part, read:

In light of the above, I am allowing this special swimming event. But please note that the weather forecasts for the District of Columbia indicate a thunderstorm on Saturday. The timing of the forecasted rainfall events would not allow sufficient time to collect samples and obtain laboratory results before the swim event. Based on past experience, it is likely that the bacterial count in the River will increase following a major rain event.

Burrell says it typically takes about 72 hours for the bacteria levels to dissipate. (In 2008, WCP wrote about the history of trying to make the Potomac swimmable.)

On its Facebook page early Sunday morning, the Nation’s Triathlon announced the cancellation of the swimming portion and said the bike and running portions of the event would go on as planned.

“Our race will go on, and with the exception of the swim, the event schedule remains nearly the same,” the Facebook post read. “We will start the event at 7:15 am via a time trial start from Ohio Drive directly into the transition area for athletes to get their bikes and start the bike course. The rest of the event will remain unchanged.”

Back in May, five million gallons of sewage spilled across the Capital Crescent Trail and into the Potomac River. DC Water is currently in the process of implementing a long-term control plan to correct this. By 2025, it expects to reduce this combined sewer overflow by 96 percent in the Potomac and Anacostia rivers and Rock Creek.

Photo by Darrow Montgomery