Bluestone Dam Drift and Debris Passage Tower

Abstract Only - The U.S. Army Corps of Engineers Huntington District (USACE) operates and maintains Bluestone Dam, located on the New River in West Virginia. During large storm events, up to 50 acres of the lake's surface is covered with drift and debris at the upstream face of the dam. Current operation of the project does not allow the overflow spillway to be used to pass this debris. Since the dam was constructed, it was necessary to lower the reservoir to the low-level outlets and manually feed the debris through those outlets. The USACE has recently completed construction of a selective withdrawal tower that can be used to pass debris through the center of the dam, over the entire range of pool elevations. Due to the unique nature of the problem and the fact that there were no similar projects to provide design guidelines, the USACE contracted ENSR to perform physical hydraulic modeling to aid in the design process. This paper presents the approach that was taken to remediate a unique problem for which no previous design guidelines existed. The paper also describes how a physical hydraulic model study was used early on in the design process to both verify and optimize the performance of the debris passage tower, transitions, and conveyance structure.