Walking through Cromwell Valley Park, one would scarcely think that the slight trickle of water running through the middle of the site could require a $4 million repair job.
But park manager Leo Rebetsky says this tiny stream, known as Minebank Run, could eventually pose a problem not just for those who enjoy the park, but for the Chesapeake Bay.
Minebank Run begins just inside the Beltway, between Joppa and Cromwell Bridge roads. It continues behind Loch Raven High School on Cowpens Avenue, running through Cromwell Valley Park and eventually flowing into Gunpowder Falls.
Several years of erosion have taken their toll on the Minebank's streambed, resulting in large-scale sediment runoffs and, more worrisome to park officials, exposure of a sewer line.
As a result, the 371-acre park has been closed to the public since June 14 and is not expected to reopen until March. However, regularly scheduled programs and summer camps are operating.
Two companies won a contract from Baltimore County to do the repairs: Environmental Quality Resources of Gaithersburg and Guardrails Etc. Inc. of Dundalk.
The stream was originally fed only by rainwater, but an increase in impervious surfaces in the Towson area has brought a much greater volume of runoff to Minebank Run, often resulting in swelling way past the stream's natural capacity, Rebetsky said.
"When we get big bursts of rain, it creates huge surges in the stream, so when the velocity picks up, it erodes the riverbeds," Rebetsky said. "The stream is just not designed to take all of that runoff."
Minebank Run, normally just 15 feet across at its widest point, will eventually deposit whatever it holds - whether sediment or sewage - into the Chesapeake Bay.
Chris Choppin, the riverbank reconstruction project manager, said, "From a water-quality standpoint, you want to make sure that you don't have any of that raw sewage leaking into the stream."
Rebetsky said the project will restore the natural course of the stream, stabilize the streambed by placing large boulders on its sides, and plant trees and shrubs on the banks to hold them in place.
In addition, new safety precautions mean the two bridges crossing the Minebank will also be replaced after heavy rainfalls have come dangerously close to flooding them.