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Dam Safety Incident Report: Benson Creek Flood

Publication number Date Published
15-11-019November 2015
VIEW NOW Dam Safety Incident Report: Benson Creek Flood (Number of pages: 53) (Publication Size: 2147KB)

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Author(s) Walther, Marty, P.E.
Description On the evening of Thursday, August 21, 2014, a rainstorm hit the recently-burned Benson Creek watershed causing considerable flood damage. As described in a previous report in this series, a computerized rainfall-runoff model was compiled to estimate what happened at each of the Wenner Lakes dams during this event.

This report presents a detailed analysis of runoff volumes and peak flows at various locations in the Benson Creek watershed; dam overtopping at the Chalfa and Rabel dams; spillway erosion at the Hawkins Dam that drained the lake; and estimated flood depths in lower Finley Canyon and in lower Benson Creek.

This analysis is limited by the clean-water calculations of the computer model. The effects of debris flows (mudslides) that occurred throughout the watershed are outside the scope of this report.
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Keywords dam safety, incident report