JOHNSON CITY, TN (WJHL) – Tennessee Valley Authority officials announced Thursday afternoon that repairs to Boone Dam would take approximately five to seven years to complete and initial cost estimates to make the repairs are around $200-300 million.
During a scheduled news conference at 2:30 p.m.in the Millennium Centre in Johnson City, TVA President and CEO Bill Johnson and TVA Vice President of Safety, River Management and Environment John McCormick spoke about the plan moving forward to get the dam back up to normal water levels.
Back in October 2014, water seepage was discovered under the embankment at the dam and an investigation revealed a series of underground pathways allowing water from upstream and downstream to cause erosion.
According to a TVA news release, if left untreated the erosion could “lead to the failure of the dam.”
Johnson said Thursday that water is currently flowing through the dam in multiple directions, and said the plan is to build a concrete wall along the earthen portion of the dam in three stages.
According to TVA, a crew will drill as many as 500 columns along the earthen dam and will inject a toothpaste-like grout to stop the water flow.
After that is completed, up to 700 columns will be drilled as deep as 350-feet and then more grout will be injected.
TVA officials said construction will start in early 2016 after the completion of an environmental review.
“The proposed composite seepage barrier should prevent further erosion and we are confident will provide the most robust, long-lasting repair at Boone Dam,” McCormick said.
According to a TVA news release, preliminary testing and site preparation work has already begun and TVA is continuing with plans to improve boat and public access to the Boone Reservoir, improve safety to boaters during the lower water levels, assist marina owners affected and will maintain a healthy fishing habitat.
Johnson said new lake access points will be built and said they will continue to monitor the fish habitat.
During the news conference, Johnson said loans will be offered to impacted business owners, but said there is a limit to what they can do.
“We realize the impact this will have on those who live and work in neighboring communities, but our overriding focus must always be the safety of our workers and the public,” Johnson said in a news release. “Lowering the lake was a prudent first step, and it’s one we’ll continue for safety’s sake until further remedial work is completed. We will do whatever it takes to correct this issue and allow the public to safely enjoy the lake. Boone Dam and reservoir are important assets for TVA and the people of this region, and we’re committed to preserving them for generations to come.”
For more information on the Boone Dam proposed repairs and updates, visit www.tva.gov/boonedrawdown, as well as follow update on @BooneRepair on Twitter.
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