About This Project

In July 2004, the upper Tenmile Creek watershed experienced a significant rainfall event. Several homes along Bentle Branch, a tributary of Tenmile Creek experienced flooding from this event. Concerned about the damage and in preparation for future flood events, the City of Duncanville commissioned a floodplain and streambank stability study for Bentle Branch. The proposed scope of work included public input on flooding concerns as well as a detailed hydrologic/hydraulic analysis of the stream. The study also included detailed floodplain and streambank stability analyses and recommendations for stormwater and stream stability improvements.

After initial field reconnaissance and channel surveys, detailed hydrologic and hydraulic computer models were created. Existing land use, fully developed land use, and existing detention facilities within the watershed were evaluated. A detailed channel stability assessment was also performed. Based on the resulting mapped floodplain and the channel stability assessment, the problem areas along Bentle Branch were identified.

Alternatives to address the streambank stability problems were formulated, tested and evaluated. Streambank stability alternatives considered included hard armor, grade and drop structures and soil bioengineering methods. Cost estimates for feasible alternatives were prepared and a recommended plan was developed. The results were documented in the final study report (large file, 75MB).

Along with the streambank stability study, a stormwater master plan was also developed. Stormwater alternatives considered included channel alterations and detention and structure modifications. Stream stability and stormwater management alternatives were also integrated into the recommended plan for Bentle Branch.

The resulting Bentle Branch Stormwater and Stream Stabilization Plan (large file, 27MB) provides the City with a plan of action for reducing flood damages, stabilizing the stream and preserving natural features in the area.