Key Takeaways from the Latest Update
The U.S. Army Corps of Engineers held a public meeting at Rough River Dam State Resort Park to provide an update on Phase 2 of the Rough River Dam Safety Modification project.
Here’s the short version:
- Construction contract has been awarded to Thalle-Bauer LLC
- Project timeline is expected to take 6 to 8 years
- Total project cost is expected to reach approximately $655 million
- Lake levels are expected to remain consistent with recent years (490’)
Most importantly, no major changes or unexpected issues were announced. The overall message was steady progress with a clear plan moving forward.
Why This Project Is Happening
This project traces back to a 2012 report that identified unacceptable risk related to the dam’s foundation, which is built on karst geology.
Karst terrain (common in this part of Kentucky) can allow water to move through underground voids, which is what led to the seepage concerns beneath the dam.
Since then, the Corps has taken a phased approach to address the issue and reduce long-term risk.
Phase 1: What’s Already Been Done
The first phase of the project focused on investigation and early stabilization work.
This included:
- Relocating Kentucky Route 79 off the top of the dam
- Performing exploratory drilling and grouting
- Studying the conditions beneath the structure
Phase 1 was completed in 2017 and gave engineers the data needed to design a long-term solution.
In 2023, additional interim safety measures were put in place — including lowering the lake to a summer pool of 490 feet — to reduce risk while preparing for Phase 2.
Phase 2: Major Construction Now Underway
The project is now entering Phase 2, which is the main construction phase.
The U.S. Army Corps of Engineers awarded a base contract of approximately $320 million to Thalle-Bauer LLC in December 2025.
This phase will include:
- Construction of a new outlet works system (control tower, tunnel, stilling basin, and channel)
- Installation of a full-depth concrete cutoff wall across the dam
That cutoff wall will extend roughly 190 feet down into solid rock and is designed to permanently address the seepage issue.
Project Timeline and Early Work
The early stages of construction will focus on preparing the site:
- Tree clearing on both sides of the dam beginning in March
- Grading and haul road construction in April and May
- General site preparation to support heavy construction
Around May, crews plan to begin building a temporary coffer dam on the lake side. This allows them to keep the work area dry while maintaining normal lake levels.
Lake Levels: What to Expect
The biggest question for most people continues to be lake levels.
According to the U.S. Army Corps of Engineers, they do not anticipate lowering the summer pool below 490 feet during the duration of the project.
That means:
- The lake should continue operating at the same summer pool seen over the past few years
- Seasonal water level fluctuations are expected to continue as normal
Traffic, Construction Impact, and Blasting
Most construction traffic will be routed through the emergency spillway rather than across the top of the dam.
This should minimize day-to-day traffic impact in the area.
There will be some blasting required during the project. When that occurs:
- Temporary rolling roadblocks can be expected
- Nearby homeowners will be notified in advance
- No structural impacts to homes are expected
Additional Project: Bridge Construction
Separately, the Kentucky Transportation Cabinet will begin construction on the bridge over the spillway.
During that project, traffic will be reduced to one lane while work is underway.
What This Means for Rough River Lake
From a big-picture standpoint, this update reinforces that the project is moving forward as planned.
- The timeline and scope are clearly defined
- Lake levels are expected to remain stable (Summer pool 490’)
- Most construction activity will happen in the background
For lake users, property owners, and visitors, the overall expectation is that it will be business as usual on the water while long-term improvements are made behind the scenes.
More importantly, this project is designed to ensure the dam continues operating safely and effectively for decades to come.
Sources
- U.S. Army Corps of Engineers
- Official project page: Rough River Dam Safety Modification Project
- Public meeting at Rough River Dam State Resort Park
- Project contractor: Thalle-Bauer LLC