Cascade Creek Hydrological Modeling and Floodplain Restoration
Erie-Western Pennsylvania Port Authority
Basin Program Funds:
Cascade Creek drains approximately nine square miles on the west side of Erie, Pa. In rain events, the stream is forced to handle a torrent of storm water that passes from an average stream width of 20 feet into a narrow channel of shale only 10 feet wide. As a result, the stream floods its banks and causes damage to the riparian corridor along its last mile before entering Presque Isle Bay. This area, known as Cascade Creek Wetlands, has been subject to years of sediment deposition. In addition, other debris such as large rocks and trees, have been carried downstream, causing the stream to alter direction. In other locations where the stream has changed course, the stream caused significant erosion.
The heavily urbanized nature of the watershed, increasingly impervious surfaces and the channelization of some sections have created severe volumes and speeds of storm water runoff at Frontier Park and the transitional wetland area found near the creek’s confluence with Presque Isle Bay. Although much of the industry discharging into Cascade Creek has left the city, the waterway still experiences degradation from remaining point source pollution, nonpoint source pollution and soil erosion. Over the years, solutions to problems such as cut banks and erosion have been employed in small sections of Cascade Creek. Manmade materials have been used to create short-term solutions that have lead to negatives effects downstream by accelerating water flow. It is imperative that Cascade Creek be studied as a watershed and all outfall pipes and storm drains be inventoried and monitored to determine the strategy and location for possible solutions such as storm water retention ponds or basins.
The Port Authority announced the project through the media, its public meetings and Internet site. The Cascade Creek Advisory Committee was formed to discuss the project and future of the watershed and will continue to monitor the watershed’s progress after the project is completed. An experienced team of consultants was selected to conduct the appropriate testing and modeling. The Erie-Western Pennsylvania Port Authority (EWPPA) documented the process and developed a report that can be used in other Great Lake watersheds. A computer model was created to delineate the floodplain and illustrate the problem areas in the stream.
At the close of this project the following tasks were completed:
- Completed necessary field work and data collection.
- Completed and ran watershed models TR55 and SWAT using BASINS.
- Developed peak flow information for 2- through 100-year storm events.
- Developed Best Management Practices (BMPs) for industrial and commercial areas within the watershed, the source of half the storm water.
- Identified the location of high levels of contaminants including oil & grease, PAHs, and sediments.
- Developed cross-sections for accommodation of various storm events.
A local engineering firm will review the computer model, which was developed by Gannon University. Once completed, the final report, presentation and model will be made available to the city of Erie public works department and other interested agencies and groups, such as the Pennsylvania Department of Environmental Protection (DEP) and the Pennsylvania-Lake Erie Watershed Association.
The Port Authority has also contracted with the Environmental Design Group (EDG) of Akron, Ohio to prepare plans and drawings for stream bank stabilization techniques along Cascade Creek. EDG has already prepared similar drawings for Frontier Park, which is located within the watershed. EDG’s work will serve as the basis for future work along the stream to combat erosion and sedimentation. Once these remaining tasks are completed, the Port Authority will host a public meeting to discuss the plans and results of the assessment.
Contact: Raymond P. Schreckengost, 814-455-7557