Skyrocketing development in Montgomery‘s Germantown area has caused “serious” deterioration in local watershed quality, some of which could eventually enter the reservoirs used for drinking water, county environmental planners say.
An increase in the number of surfaces such as rooftops, sidewalks and parking lots is making it more difficult for rainwater to find its way back to streams, county environmental planner Steve Findley told The Examiner.
“When water lands on these surfaces, it picks up pollutants that might have been deposited on them” Findley said. “Soil and vegetated areas tend to filter out hydrocarbons, like oil and gasoline, heavy metals from engine systems, and road salt. Now when we add these impervious man-made surfaces, it means a lot of that water that would have been filtered is no longer being filtered.”
Findley said the county’s Department of Environmental Protection had graded all except one Germantown watershed good or fair during their first evaluation in 2001, but that by 2006, those that were previously rated “good” had sunk to “fair” ratings, and the watersheds with “fair” ratings were deemed “poor.”
Montgomery environmental officials use the number and kind of existing fish and aquatic insect species to evaluate the health of a watershed. “This is consistent with other areas rapidly urbanizing across the country,” Findley said.
Upper Montgomery County, including Germantown, has been the site of rapid growth in recent years. Germantown’s population jumped from about 580,000 in 1980 to about 950,000 in 2007, according to census data.
County planners are currently working on updates to Germantown’s master plan, and planning board members have asked them to incorporate remedies for deteriorating watershed quality into their planning process, planning board spokeswoman Valerie Berton said.
“There are ways to address water quality concerns with greater tree cover and increased storm water management efforts that will still allow us to shoot for increased density in the area,” Berton said. “We’re looking at things like structured parking lots and multistoried buildings that will reduce the amount of impervious surfaces.”
Findley said watershed quality is a concern because some of Germantown’s streams drain directly into Little Seneca Lake, which is used as a reservoir for emergency water supply. During droughts, water is released from the lake to add to reservoirs used for drinking water.
