The Potomac River is dirty. These lowly little freshwater creatures could be what cleans it

A scientific dive conducted by Sam Peltz and Nova West

"The 2-year-old Lamp Mussels, a freshwater cousin of oysters, were recovered this week from a small demonstration project being conducted by the Potomac Riverkeeper Network at the National Harbor Marina in Prince George's County, Maryland. Divers checking the mussel project under the docks found conditions so polluted and murky they were nearly blinded while trying to recover samples. But in a little over an hour, the mussels brought to the surface significantly clarified an aquarium tank filled with dirty water that was placed on the dock..."

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