BLUESTONE DAM EDGES CLOSER TO COMPLETION

BY CHARLES MINSKER, Huntington District

The makeover at Bluestone Dam has been a slow process, but the final part of the process is now underway. Located on the scenic New River in southern West Virginia, the dam is a massive concrete structure built in the 1940s to reduce flooding across the state. It’s enjoyed a long history of success, preventing more than $6 billion in flood damages during its lifetime. However, a challenge to the dam’s ability to withstand occurred in the late 1990s.

For 20 years, the U.S. Army Corps of Engineers (USACE) has worked to bring the dam up to modern safety standards as part of its Dam Safety Assurance project, accomplished through four phases that entail the building of a massive concrete thrust block to strengthen and stabilize the dam, with a unique system of more than 500 rock anchors directionally drilled deep into the bedrock to help the dam resist the intense forces of extreme stormwaters.

Aerial photo of Bluestone Dam. Located on the scenic New River in southern West Virginia, the dam is a massive concrete structure built in the 1940s to reduce flooding across the state.

USACE Photo

Work has begun on the final phase that involves redesigning and strengthening the stilling basin, the area just below the dam that includes stone and large concrete baffles that decrease the energy from the water before it continues downstream. Studies have shown that an intense storm might wash away the stone in that basin and cause erosion, undermining the dam.

Huntington District Commander Col. Jason Evers said, “To keep that from happening, we’re going to use concrete to armor the stilling basin. The dam has to keep water moving while that’s happening, so we’re putting cofferdams in the middle of the basin. That way, we can dewater half of the basin and do the work while the other half continues to keep the river flowing.”

The work was made possible when Congress passed the Bipartisan Budget Act in 2018, which appropriated $17 billion to USACE for infrastructure projects. That included all the funds required for the Huntington District to complete this phase of work.

The district was challenged to take this unprecedented opportunity to “move dirt” and to ensure projects like this are implemented quickly.

Senior project manager Aaron Smith said, “The team at Bluestone Dam took that challenge to heart and advanced the start of the primary spillway work by over four years. In the past year alone, the Corps has awarded five contracts to start this work. We can see significant progress already, as the installation gets underway of a $22 million temporary cofferdam by Brayman Construction. The goal is to have this cofferdam in place so we’re ready to begin the stilling basin modifications next year.”

The cofferdam will form a concrete dividing wall that will divide the basin: One side will continue normal water flow while the other side is lined with concrete and larger concrete baffles will be constructed. Once one side is finished (including the installation of a permanent dividing wall, allowing easy dewatering of the area for future inspections), the process is reversed.

When complete, the dam will be able to handle most catastrophic weather events, and will continue doing the job it has done so well for the past 70 years: protecting the residents who live downriver from its towering walls.