Gwynns Run Water Pollution Control Facility

Debris Removal System Upgrade, City of Baltimore, MD

The Gwynns Run Water Pollution Control Facility (WPCF) is a 70,000 square foot offline stormwater treatment facility that is located at the confluence of Gwynns Run and Gwynns Falls, southwest of the City of Baltimore.  Gwynns Run is a tributary of Gwynns Falls, which in turn is a tributary to the Patapsco River.  PEER helped to revolutionize the existing Net-Cassette trash collection system that was installed on 10 openings of an L-shaped concrete structure, which had been vandalized and was therefore inoperable since 2008.

The existing trash collection racks on the stormwater treatment pond riser structure were also ineffective, clogging the orifices and filling all three ponds (i.e. forebay, wetland basin, and the main pond) with sediment.

PEER was awarded this project to:

  • Perform on-site investigation and evaluation of the existing system.
  • Review the hydraulic and hydrological data for the stream and the ponds.
  • Evaluate appropriate debris collection options based on their effectiveness in trash removal, minimum maintenance, cost-effectiveness, vandal-proof features, and constructability.
  • Use bathymetric data to estimate the quantity of sediment in the ponds and methods and cost of dredging of the ponds.
  • Prepare design drawings, specifications, cost estimates, and bid documents for construction of the selected debris removal system at the entrance of the ponds and Gwynns Run.

As a result, PEER installed a new net bag system on each of the 10 openings under the bridge with special features and a security camera system to prevent vandalism.