@nprofile1q...

Please tell me that they actually filled it with Potomac water. Back in 2010 they were trying to mitigate cyanobacterium blooms and it was the hurricanes of 2011 that get the credit for actually clearing the blooms!
https://www.mwcog.org/about-us/newsroom/2011/09/15/potomac-river-algae-largely-dissipated-algal-blooms-potomac/