Skip to main content
U.S. flag

An official website of the United States government

Simulations of flow and prediction of sediment movement in Wymans Run, Cochranton Borough, Crawford County, Pennsylvania

October 14, 2011

In small watersheds, runoff entering local waterways from large storms can cause rapid and profound changes in the streambed that can contribute to flooding. Wymans Run, a small stream in Cochranton Borough, Crawford County, experienced a large rain event in June 2008 that caused sediment to be deposited at a bridge. A hydrodynamic model, Flow and Sediment Transport and Morphological Evolution of Channels (FaSTMECH), which is incorporated into the U.S. Geological Survey Multi-Dimensional Surface-Water Modeling System (MD_SWMS) was constructed to predict boundary shear stress and velocity in Wymans Run using data from the June 2008 event. Shear stress and velocity values can be used to indicate areas of a stream where sediment, transported downstream, can be deposited on the streambed. Because of the short duration of the June 2008 rain event, streamflow was not directly measured but was estimated using U.S. Army Corps of Engineers one-dimensional Hydrologic Engineering Centers River Analysis System (HEC-RAS). Scenarios to examine possible engineering solutions to decrease the amount of sediment at the bridge, including bridge expansion, channel expansion, and dredging upstream from the bridge, were simulated using the FaSTMECH model. Each scenario was evaluated for potential effects on water-surface elevation, boundary shear stress, and velocity.

Publication Year 2011
Title Simulations of flow and prediction of sediment movement in Wymans Run, Cochranton Borough, Crawford County, Pennsylvania
DOI 10.3133/ofr20111223
Authors Elizabeth Hittle
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2011-1223
Index ID ofr20111223
Record Source USGS Publications Warehouse
USGS Organization Pennsylvania Water Science Center