Carpentier Creek Study

Among the project's goals were modeling the creek main channel and major tributaries, identifying illegal stormwater discharges, creating development standards, and generally supporting the MS4 in obtaining its NPDES Phase II permit. The study investigated the impacts of recent widespread development on existing main channel and tributary capacities. The format needed to be used in meetings and presentations for clients and City officials. Large aerial images and online resources were used in obtaining the information needed for the project, which was then imported into AutoCAD and linked back to websites and MS Word documents to cross-reference the information with the maps. The project included developing a hydrologic model for the watershed using TR-20 and HEC-HMS and modeling the hydraulic surface profile of Carpentier Creek using HEC-RAS. These models were used to locate areas of potential flooding, critical areas with erosive stream velocities, and hydraulically inefficient bridge/culvert structures. Multiple modeling scenarios were analyzed, incorporating existing and proposed detention facilities within the watershed, as well as backwater effects from various stages of the Ohio River. The project involved extensive coordination with a local watershed action group, the Vanderburgh County SWCD, IDNR, and the Vanderburgh County Engineer's Office.

The study included the analysis of non-point source agricultural pollution along channel banks and its effects on existing channel capacities. The project included developing a hydrologic model for the watershed using TR-20 and HEC-HMS and modeling the hydraulic surface profile of Carpentier Creek using HEC-RAS. These models were used to locate areas of potential flooding, critical areas with erosive stream velocities, and hydraulically inefficient bridge/culvert structures. Multiple modeling scenarios were analyzed, incorporating existing and proposed detention facilities within the watershed, as well as backwater effects from various stages of the Ohio River. The project involved extensive coordination with the Westside Improvement Association (a local watershed action group), the Vanderburgh County SWCD, IDNR, and the Vanderburgh County Engineer's Office. Project elements also included the preparation of a stormwater master plan for future development within the watershed, an accepted flood insurance study model, and construction cost estimates for proposed improvements. Recommendations including construction cost estimates for improvements to the existing waterways were provided, as well as methods for reducing sedimentation along the channel profile.