North Green Springs Valley Drainage Study

This project was generously provided by Lochmueller Group, a civil engineering firm located in Evansville, Indiana. North Green Springs Valley is a small residential subdivision located in Newburgh, Indiana. Documented as far back as 1974, North Green Springs Valley subdivision and its residents have been experiencing extreme flooding due to inadequate conveyance in the primary drainage channel. A site visit indicated significant debris in the stream and evidence of erosion and water damage. The flooding poses a threat to the residents and their homes. The focus of this project was to complete a professional hydrologic and hydraulic study of the stream. The hydrologic study quantified the magnitude of a 50-year flood event. A hydraulic model of the study reach was used to simulate existing field conditions, including two bridge structures using the United States Army Corps of Engineer’s Hydrologic Engineering Center River Analysis System (HEC-RAS). New renditions of the model were created to simulate several design alternatives by altering model input parameters. Based off the new models, several design alternatives were then proposed that restrict the water flow to the banks of the stream and thus reduce flooding risk.