Tiny, Non-Native Mussels Could Soon Impact Our Drinking Water

BALTIMORE (WJZ) — It's a foreign invasion, and Baltimore is making a stand at its reservoirs.

Alex DeMetrick reports the source of much of our drinking water could be impacted by a tiny, non-native mussel.

People who operate Baltimore's reservoir system have a big worry -- even though it can fit in a small jar -- zebra mussels, a non-native species, could be a concern.

"There's the potential for an accidental introduction into our water supply system, our source water reservoirs," said Baltimore DPW watershed manager Clark Hawell.

The Internet shows what zebra mussels did in the Great Lakes, where they were first released in ships' ballast water, and have been spreading ever since.

In 2008, two zebra mussels were found above Conowingo Dam. By 2014, thousands were reported in waters off Harve de Grace.

"Females can produce tens of thousands to hundreds of thousands of larva a year, and they breed for a long period of time," said Matt Ashton, DNR biologist.

They cling like barnacles to all hard surfaces, clogging water pipes and intakes.

"Blockages as a result of the zebra mussels lining the inside of the piping. And so we are taking steps to limit that threat," said Hawell.

Boats spread zebra mussels from infected waters by hitching a ride on trailers and boat motors. To keep them out of reservoirs, a new rule is going into effect.

"If you are going to use your boat in one of the city reservoirs, that you can use it no other bodies of water in Maryland," Hawell said.

Once they establish, there's no getting rid of zebra mussels.

If they make it into the reservoirs, their huge numbers could affect the taste of water, and clearing them from the system's infrastructure will be a new and constant expense.

To control boat use on the reservoirs, an owner must receive a permit and sign a pledge to keep their boat out of other Maryland waterways.