Carroll County's participation in a statewide survey of watershed areas will focus on two streams, one of which feeds into Liberty Reservoir, the source of drinking water for 2 million people in metropolitan Baltimore.
In addition to Middle Run in Deer Park, a feeder stream to Liberty, the Maryland Conservation Corps will study Piney Run Stream, the primary source for Piney Run Reservoir in Sykesville. The county plans to build a $14 million treatment plant at Piney Run to augment the water supply in South Carroll.
The survey aims to determine if erosion and increased sediment have occurred along streams throughout Maryland and what remedy is possible. The corps is overseeing the survey for the state Department of Natural Resources.
"We need to determine how much erosion we have and where we can do" stream bank repairs, James Slater, Carroll's environmental compliance specialist, said yesterday in a meeting with the county commissioners. "Our priority is streams that flow into the water supply. The faster the sediment load is in the streams, the faster it will fill up reservoirs."
Inadequate storm-water management or faulty sediment control can cause bank erosion. Sediment can build up in streams and eventually reach reservoirs, making treatment of drinking water more cumbersome.
The county will mail letters to residents whose properties lie along the streams and request permission to walk along water banks and assess the overall appearance.
Slater said the survey, expected this summer, should pose no inconvenience to homeowners. Students, trained by DNR, will collect much of the data.
Slater asked for cooperation from residents who should be mindful that streams on their properties affect the quality of the public water supply.
"Streams that run through private property benefit the entire population because they influence water quality at the reservoirs," Slater said.
The study is limited to stream banks and will not assess water quality, but will look at stream habitats because erosion and sediment affect plants and wildlife.
Local efforts should help determine the overall condition of watersheds, land that surrounds and protects the drinking water supply for millions of residents, said Slater.
Liberty is the source of drinking water for residents of Baltimore and the surrounding metropolitan counties, including 7,000 homes and businesses in Carroll County.
Funding for erosion control and stream bank repair is often available through grants from the federal government, which requires the surveys, Slater said. Grants also might be available for the cost of the survey.
Slater will meet with the eight Carroll towns this month to ask for municipal participation in the survey.
"Every jurisdiction has a discharge permit for what comes out of its storm water systems," Slater said. "Everything out of that pipe has to be of a certain quality because ultimately runoff ends up in a stream."
The state conservation corps has offered to do an assessment of the streams for the county at a cost that Slater said he expects would be reasonable.