Qualitative evaluation of the effects of changing watershed land uses on the hydrology, channel morphology and historical uses of Valley Creek, Valley Forge National Historical Park, Pennsylvania
Reed WB. 1990. Qualitative evaluation of the effects of changing watershed land uses on the hydrology, channel morphology and historical uses of Valley Creek, Valley Forge National Historical Park, Pennsylvania. NPS/NRWRD/NRTR-90/08 (NPS D-17). National Park Service, Water Resources Division. Fort Collins, CO
The objective of this report is to provide a qualitative evaluation of the hydrology and geomorphology of Valley Creek necessary for developing effective bank stabilization strategies. Valley Creek flows for approximately 1 1 ,000 feet through Valley Forge National Historical Park to its confluence with the Schuylkill River. Valley Creek at Schuylkill River has a watershed of 23.25 square miles. The watershed has undergone extensive land use changes during the last 20 years resulting in changes in Valley Creek flow characteristics and associated fluvial processes. Within the park, between the covered bridge and the upper forge site, Valley Creek once migrated back and forth within a very narrow valley. In recent times, the stream has been confined by alternative uses of the valley floor, and now threatens these uses as it continues to adjust to changes in watershed conditions. Of particular concern is the potential for the undermining of Route 252 and underlying forced sewer main. In general, it appears that present-day changes in land use from agriculture to lowdensity residential areas and corporate centers may have less impact on the hydrology of Valley Creek than did the previous transition from agriculture to high-density residential areas and industrial parks. Therefore, if present-day changes in land use continue, the discharge characteristics of Valley Creek will deviate very little from existing conditions. However, channel geometry will continue to widen in response to previous changes in stream flow (especially flood peaks) caused by historic changes in watershed conditions. Based upon these conclusions, slope protection and erosion control efforts should be designed for current streamflow conditions and will need to anticipate future changes in channel geometry. Conceptual slope protection and erosion control designs for the upper forge site and for the reach between the covered bridge and the upper forge site are presented in Appendix A.
- Type
- Published Report
- Authors
- Reed, William
- Date of Issue
- 1990-10
- Publisher
- National Park Service, Water Resources Division
- Units
- VAFO , WRD
- Keywords
- Bank stabilization, Channel Morphology, Clemson, Erosion Control, Geomorphology, historical uses, Hydrology, land use changes, peak discharge, qualitative evaluation, slope protection, Stream Restoration, Valley Creek, Water Quality, Watersheds, WRBIB