Background Remnants from Hurricane Harvey in 2017 hovered over Central Texas for several days, creating flooding throughout the region that damaged structures such as the historic Buescher State Park Dam. The dam’s structural integrity was threatened as several feet of material eroded away during the rain event, and the Texas Parks and Wildlife Department (TPWD) needed to find an immediate solution that would preserve the historic structure and protect a critical economic resource. Halff was contracted to perform emergency repairs that stabilized the dam and prevented a breach. After the emergency repair and understanding the importance of a more permanent solution, TPWD again contracted Halff to implement detailed construction plans, specifications, and cost estimates for rehabilitating the dam to comply with current regulations, which included improvements to the dam’s embankment and principal spillway. The newly designed Buescher State Park Dam retains historical homages to the original structure, such as the native red sandstone, while offering a structure that meets current standards and can preserve the economic importance of the park for years to come.
Impact By finding a permanent solution for the dam, TPWD has been able to reopen its recreation program, which will ultimately help lift the local economies of Smithville and Bastrop. Halff worked with the U.S. Army Corps of Engineers (USACE) to improve stream functionality with a riffle-pool sequence. Once fully established, this will provide an additional habitat for the native amphibians and birds within the park. Halff also developed an innovative approach to reduce potential impacts to endangered species, particularly the Houston toad, which included measures like taking a traditional silt fence and repurposing it to develop toad exclusion fencing. Design enhancements for the new structure included installing a sharp-crested, straight drop principal spillway, training/retraining walls, grading, native stone rock riprap and stream enhancements. Technical Aspects • Spillway improvement features more than 340-feet of retaining walls, a stifling basin, and a 200-foot sharp crested weir and spillway chute • Dam design and dam breach analysis
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December 2023
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