The US Army Corps of Engineers Louisville District announced on Thursday, March 17 that the estimated completion date for the remediation work on Rough River Dam has been delayed to 2021 or 2022.
Jeff Esterle, dam safety program manager for the US Army Corps of Engineers Louisville District, spoke during the Corps’ annual public meeting on the dam remediation project to update the public on the status of the project and the work that has been done so far.
The dam remediation project began in 2012 when the Corps start planning for how best to address issues caused by Rough River Dam’s karst foundations, according to Esterle.
As a result of the karst features in the dam’s foundations, voids can form in the rock foundation, allowing water to carry soil through the holes, potentially causing the dam to fail.
To ensure the dam’s stability and longevity, the Corps of Engineers began Phase 1 of the dam remediation project, which involved relocating Highway 79 (Phase 1a, which has been completed), and injecting grout into the rock below the ground surface of the dam’s foundations to fill the aforementioned voids (Phase 1b, which is currently ongoing), according to Esterle.
During the grouting phase, the Corps also investigated to determine whether a more permanent solution would be required to prevent water seepage through the voids in the dam’s foundations, and the Corps determined a continuous concrete cut-off will have to be installed to ensure the dam’s stability (Phase 2), Esterle said.
The grout, while improving the condition of the dam, is not a permanent solution because it cannot fully penetrate and fill every crack in the foundation completely, according to Esterle.
A cut-off wall, constructed from the crest of the dam down through the soil, will remedy this by preventing any water from seeping through the dam’s foundations, Esterle said.
Currently, the Corps of Engineers is awaiting approval from the federal government to move forward with Phase 2 (the construction of the cut-off wall).
Because the federal budget is formulated on a two-year cycle, the Corps of Engineers hopes to receive funding for the Rough River Dam cut-off wall construction during the Fiscal Year 2018 budget cycle and begin construction either in 2018 or 2019.
Provided approval is granted to begin Phase 2 earlier, however, Esterle said, the Corps may be able to begin work on the project as early as 2017.
Additionally, the Corps of Engineers announced Thursday that, as of now, there are no plans to change Rough River Lake’s seasonal lake levels.
The Corps of Engineers will host another public meeting in 2017 to further update the public on the progress of the dam remediation.
For lake information and to keep up with events and the dam remediation project at Rough River Lake, visit the US Army of Engineers, Rough River Lake website at http://www.lrl.usace.army.mil/Missions/CivilWorks/Recreation/Lakes/RoughRiverLake.aspx or Facebook page at https://www.facebook.com/pages/Rough-River-Lake/194425466082.
Reach Matt Lasley at 270-259-9622, ext. 2015.