Downingtown, PA -- The Department of Conservation and Natural Resources (DCNR) plans to begin conducting an annual winter drawdown next month of the 535-acre lake at Marsh Creek State Park.
The drawdown prevents damage to the park facilities; increases storage capacity for winter storm events; and subsequently reduces risk for recreational users and downstream communities.
Solid ice cover at normal summer pool can damage the dam infrastructure, docks, and other access infrastructure.
The DCNR’s standard practice has been to initiate a three-foot drawdown of the reservoir.
However, a three-foot drawdown would expose approximately 10 acres of bentonite material deposited in the lake during an inadvertent return associated with the Sunoco Mariner East II pipeline construction project on August 10, 2020.
Hazard Communication Safety Data Sheets for the bentonite material notes inhalation risks from dry material.
After consultation with experts from the Department of Environmental Protection (DEP) and the Department of Health (DOH), DCNR has decided to initiate a one-foot drawdown to provide flood storage capacity, but with consideration to limit the extent of bentonite material already deposited during the inadvertent return.
The DCNR will be updating the status of the drawdown and observations to the DEP and DOH.
The cove that contains the deposited bentonite material is marked with buoys and is closed to visitors using watercrafts.
Additionally, the DCNR requests that visitors stay out of the shoreline areas along the cove to reduce exposure to any exposed bentonite material.
Operation of the dam at Marsh Creek State Park is governed by the Operation and Maintenance Manual for Marsh Creek State Park Dam (March 1975), which also references constraints of a Delaware River Basin Commission Decision.
The manual notes flood control as one of multiple purposes of the dam and recommends an annual drawdown after the recreation season. This practice has been followed for 47 years.
MEDIA CONTACT: Marsh Creek Park Office, 610-458-5119