Boone Community Q + A

The following includes a list of Boone Dam current and historical questions and answers. The questions come from members of the public via the Boone e-mail program through our monthly newsletter, our Twitter feed and other directly submitted questions. (Updated October 19, 2018)

Topic: Construction/Schedule

 

How deep/big is the wall?

The wall is a minimum of 24 inches thick, approximately 840 feet long, and varies in depth from approximately 100 to 180 feet below the working surface.

How long will it take to build?

TVA will complete the wall by May 2021 and is on schedule to return the reservoir to the normal operating guide curve by July 2022.

How will you build it?

The wall will be built using overlapping, reinforced construction elements.

When will the wall construction begin?

Mobilization will begin in Fall 2018. A tremendous amount of pre-work is involved in preparing the site ahead of time for construction. Some of that can be seen already in terms of the laydown yard construction and new employee parking lot at Boone Dam. Construction will begin in May 2019.

How much have you spent so far on the Boone Dam repair project?

So far, we have spent more than $120 million and we remain on budget.

Why was the July 2015 original cost estimate changed from $300 million to $457 million?

The $300M was a benchmark from various U.S. Army Corps of Engineers jobs to build a cut off wall. The complete $457M project number announced in 2017 includes a significant amount of additional work that makes Boone very safe and robust, such as the buttresses up and down stream and the high and low mobility grouting programs.

This increase will help ensure the commitment to return Boone Lake to the community while maintaining the safety of the downstream public.  Budget changes are normal as the design & construction progresses and will be refined throughout the project. 

Are you finished with the grouting?

We have completed the grouting necessary for stability of the earthen embankment during construction of the cutoff wall. Quality of the repair is one of our Top Priorities in this project. To ensure the repair is of the highest quality and robust as it can be, we are doing some additional grouting this fall. However, this does not indicate any additional problems and it is not tied to the timing of cutoff wall construction and the subsequent schedule for the refill plan.

What is the cost of the Treviicos-Nicholson contract?

TVA signed non-disclosure agreements with each of the companies involved. However, the cost is included in the $457 million total project budget, and we remain on track to meet that budget.

Who else bid?

We received multiple competitive proposals. Again, TVA signed non-disclosure agreements with each of the companies involved.

When was the contract awarded?

The notifications for selection and non-selection were made July 31, 2018.     

How many local workers will be used?

We will have a total work force of approximately 200 people when we are running at full capacity and certainly a portion of those are local.

Will the wall construction be happening 24 hours-a-day, six-days-a-week, as previous parts of the project were?

We expect there will be phases of the wall construction that will operate 24 hours per day.

What is the status of the Boone Dam project? Are there any material changes in the expected cost or schedule?

We’ve completed some work on reinforcing the upstream and downstream sides of the earthen embankment. After completing the majority of the early grouting work, this current phase of the project is in preparation for starting construction of the composite seepage barrier later this year. We’ve named Treviicos-Nicholson Joint Venture to construct the underground cutoff wall. We are still targeting completion of the project in 2022 at a cost of up to $457 million.

Has TVA built a cutoff wall similar to the one planned for Boone Dam? 

TVA has completed seepage barrier projects in the past but has not built a composite seepage barrier, including a cut-off wall, of this magnitude.

What experience does the contractor Treviicos-Nicholson Joint Venture have specifically on construction of dam cutoff walls? 

Numerous projects and Treviicos was a key partner in the Wolf Creek Dam Repair and Nicholson has worked on multiple TVA dams including Boone.

Do they have the required equipment and dedicated crews?

Yes.

Are they currently working other dam repair or construction projects that might take priority over Boone Dam?

No.

When will the new contractor be able to get the required equipment set up and start on the first excavation trench for the cutoff wall? 

May 2019.

When will the first cement be poured for the first section of the wall?

May 2019.

Will TVA be providing a detailed schedule for construction of the cutoff wall at the September 25th meeting, with monthly milestones? Will TVA report progress to the public on a quarterly basis?

Yes. TVA will provide the major milestones in the remaining work and update the public monthly via our public communication channels including this web site.

TVA has made recent statements (2018) that they are ahead of schedule, that the cutoff wall could be completed within 18 months or sooner with contractor incentives, and that a completion by 2020 or sooner is possible.  Are these achievements still being pursued and have they been confirmed?

The berms and procurement of the cutoff wall contractor were completed ahead of the initial project schedule. TVA has never stated that the wall will take only 18 months to complete. We will complete the wall by May 2021, and we have consistently stated that we are on schedule to return the reservoir to the normal operating guide curve by July 2022.

What is the estimated number of sections to be poured for the roughly 800 ft of cutoff wall, and how long and deep will the sections be excavated?

Approximately 300 sections or elements, generally 100 to 180 feet deep, approximately 835 feet in total length.

Roughly how long will it take to dig and clean out each section, and how many sections will be completed/filled with concrete each month?

Estimates vary significantly by location, geometry of the element and geology along the profile.

Will the contractor use multiple digging machines initially to speed up the wall construction process?

Yes.

Will the contractor be working 6 days a week, two shifts a day, until the wall is completed as originally promised by TVA President Bill Johnson?

The contractor is expected to work 5 days per week/24 hours per day with a day shift on Saturday once the production of the wall starts.

What is the expected start to finish schedule for completion of the wall (i.e. 800 ft, 10 ft/section, 80 sections, 6 sections/month, 14 months total).

The current physical wall installation schedule is May 2019 to May 2021. This timeframe does not include any required infrastructure construction or the closeout of documentation. It also does not consider the observation and testing period necessary after the completion of wall construction. As previously stated, the project is expected to be complete and the lake returned to its normal operation by July 2022.

What specific incentives are specified in the contract for early completion of the wall?

Due to confidentiality terms and agreements, the specific details of the contract, including incentives, will not be discussed publically.

Is the project on schedule?

Yes. We are on track, on scope and on schedule. Since July 2015, construction of the composite seepage barrier has been moving forward on schedule for completion in calendar year 2022.

When will it be finished?

We are on schedule for completion of construction in calendar year 2022. This is within the estimated completion timeframe we first announced in July 2015.

How much work has been done to date?

Work to date includes:

  • Completing the planned Low Mobility Grout (LMG) holes intended to contain the slurry for the part of the composite seepage barrier.
  • TVA has completed the upstream and the majority of the downstream High Mobility Grout (HMG) effort also intended to contain the slurry during wall installation.
  • Since December 2015, approximately 800 dual purpose holes have been completed to help maintain stability during construction and to feed data into the ultimate design of the composite seepage barrier.
  • The TVA continues to assess the results of the grouting program.
  • We also have conducted dye testing to replicate the testing prior to grouting and those tests were favorable.
  • We’ve made some timeline modifications to the sequencing of interim construction activities to continue to move towards completion of the project as projected.
  • Slurry cell testing of the previous grouting effort is ongoing.
  • TVA moved the upstream & downstream berm construction forward in the schedule.

Why did you build berms?

The berms provide additional stability for the earthen embankment and an improved working surface for wall construction. Construction on the upstream and downstream berms was pulled  ahead to provide additional strength to the dam as construction resumes.

This sounds like a lot of unplanned activity or changes in the work plan. Were there problems with the original plan?

Since the start of the project, certain aspects of the repair work (i.e. workforce on site, grouting techniques, order and sequence of repair activities, etc.) were designed with the flexibility to be refined or modified as needed as new data are gathered. The temporary construction stoppage, resequencing of planned activities, and other such refinements are expected in these types of major construction projects and were anticipated in the estimated five-to-seven year timing of the Boone Project plan.

Will there be other changes to the work plan?

The project remains on schedule and we will continue to monitor data to make any additional adjustments necessary to ensure the safety the public and quality of the repair.

Topic: Boone Dam Safety

 

Is Boone Dam safe?

Boone Dam is structurally sound. Safety of our employees and the general public is our top priority. We continuously monitor the dam and surrounding structures so that we’ll know if there are changes in its condition. The current project began after investigations indicated that, under normal operating levels, erosion was occurring deep underneath the earthen dam and could worsen if not repaired, threatening the stability of the earthen portions of the dam.

Why didn’t the dam safety program find this problem?

Actually, it did. Plant employees trained to identify dam safety issues—part of the overall dam safety program—were the first to identify this issue.

Will what happened at Boone happen at other TVA dams?

TVA has a robust dam safety program with comprehensive inspections and monitoring. We’re also performing “health checks” on all 49 dams to thoroughly analyze their conditions.

TVA is fully committed to the safety of the public we serve. We have numerous monitoring systems, as well as routine health checks and inspections, to maintain awareness of the condition of our facilities. Although dams are complicated structures that require periodic maintenance, the situations we have encountered at Pickwick and Boone are separate and distinct issues and we are taking the necessary steps to correct them.

Have other TVA dams had the same issue as Boone?

Yes. At other dams with seepage in the past, the source has been identified, and the dams have been successfully repaired. Those include TVA’s Tims Ford, Bear Creek, and Little Bear Creek Dams. In addition, the U.S. Army Corps of Engineers’ Wolf Creek Dam had similar issues which were repaired in 2013.

How are your other dams doing?

Overall, our dams have held up exceptionally well over decades—and sometimes, centuries—of use. Like any “machine,” dams do require preventative maintenance. Our dam safety program is designed to help us identify any potential issues very early and correct them before they could ever cause a safety issue. TVA has spent more than $390 million on river dam improvements since 2010.

What can you do to guarantee this will not happen in the future?

While no one can guarantee zero future risk, this fix will minimize risk as much as possible. We recognize our responsibility to maintain and operate all of our facilities in a way that protects the health and safety of the public. In addition to regular maintenance, we have monitoring and assessment programs in place to quickly identify any potential issues in their earliest stages, which allows us to correct them as quickly, effectively and safely as we can.

How will people be notified if the dam fails?

In the highly unlikely event that a TVA dam were to fail, there are Emergency Action Plans (EAPs) in place to quickly notify response personnel and alert the public. TVA works with counties, states, National Weather Service, and a host of other partners to prepare for such an event. Boone Dam is monitored 24/7 by highly trained engineers. This provides TVA the ability to react to changing conditions day and night. If any of the monitoring signals an event, TVA will immediately notify the affected counties to begin evacuations, and the National Weather Service to broadcast a Dam Failure Flood Warning to the public.

What would be the real impact to those living downstream of Boone Dam?

If the erosion of the embankment were to continue and the dam were to fail, the impact downstream would be significant.  Homes, businesses and recreational areas would be flooded and thousands of lives would be placed in danger. It is for these reasons that we must maintain lower reservoir levels while we safely correct the seepage problem.

First, Pickwick had an issue, now Boone… are all of TVA’s dams having problems?

The issues faced at Pickwick and Boone are different, and TVA is fully committed to the safety of the public we serve. We have numerous monitoring systems, as well as routine health checks and inspections, to maintain awareness of the condition of our facilities. Although dams are complicated structures that require periodic maintenance, the situations we have encountered at Pickwick and Boone are separate and distinct issues and we are taking the necessary steps to correct them.

Topic: Boone Dam Seepage

 

What is really happening at the embankment?  What’s the root cause?

The natural karst geology of the area has allowed water to gradually erode the foundation soils over time, creating additional pathways for groundwater in and under the embankment. If left uncorrected, this erosion could eventually undermine the foundation of the embankment and lead to the failure of the dam.

Why wasn’t the dam built correctly to begin with?

In dealing with the complexities of karst geology, Boone Dam was constructed using the best construction methods available in the early 1950s. Over time, foundation soils under the embankment have slowly eroded causing water pathways to develop. The proposed repair will prevent further erosion.

What can you do to guarantee this will not happen in the future?

While no one can guarantee zero future risk, this fix will minimize risk as much as possible. We recognize our responsibility to maintain and operate all of our facilities in a way that protects the health and safety of the public. In addition to regular maintenance, we have monitoring and assessment programs in place to quickly identify any potential issues in their earliest stages, which allows us to correct them as quickly, effectively and safely as we can.

As far as the sinkhole and the seepage that was originally found, how were these both repaired?

The sinkhole was repaired with low mobility grouting. The cut-off wall mitigates the seepage from the reservoir.

Is there currently any indication of seepage either within, around, or below the embankment? If there is currently no specific evidence of seepage, what specific evidence does TVA have that warrants further repair of the dam?  Does TVA have technical data or evidence to support further repairs?

Yes, there is continuing evidence of seepage which is why the cutoff wall must be completed as part of the composite seepage barrier. No further repairs to the embankment are currently anticipated beyond the construction of the cutoff wall and crest restoration.

Were there specific caverns or crevices discovered within the karst geology below the embankment, or other instability issues discovered during the core drilling and grouting process? 

During the exploratory drilling and grouting efforts, we did confirm the presence of karst features (enlarged bedding planes, open bedding planes, etc.)

What did TVA find in performing the Extent of Condition evaluation of other TVA dams for seepage/karst geology problems similar to Boone? Were there other TVA dams identified with similar karst geology and/or seepage issues? 

No other TVA dams were identified to have problems similar to Boone because geology varies locally/regionally. In karst terrains, that geology is even more variable.

Topic: Environment

 

Why has TVA not followed through with the 2016 EA plan for "annual and periodic" removal of significant lakebed navigation hazards?  The trees are 30 feet high in many areas.

The Environmental Assessment assesses potential environmental impacts and stated that TVA’s objective in managing vegetation is to ensure that there are no safety or navigation hazards once waters are returned to normal levels. The EA states that vegetation growth would be managed on an annual or periodic basis.  TVA intends to limit the frequency of mechanical equipment in the lakebed to reduce mechanical erosion impacts.

TVA identified two sites on TVA lands near the dam to use as construction support areas to store clean fill dirt and soil from construction. This will impact traffic Minga Road and recreation on the nearby Earl Light Tract. Can’t TVA do something else?

TVA is continuously seeking options to mitigate or lessen local project impacts, and one of the areas currently being re-assessed is the need to use Earl Light for spoils disposal. We will notify the public of any change in plans for the potential use of this area for spoils disposal.

Topic: Refill Plan and River Management

 

What is TVA’s plan/schedule for refilling the lake? 

The lake will have a period of fluctuation, potentially up to summer pool following completion of the barrier, planned for 2021. Once the data is reviewed and submitted, the lake will be returned to the normal operating guide curve in 2022. When would the refill process start, and has that been integrated with the new contractors cutoff wall repair completion schedule? Refill is part of the overall project plan and will begin after completion and verification of the final element.

When will you begin refilling the lake?

The observation period will begin after construction of the composite seepage barrier, which is scheduled for completion by May 2021. We will notify the public before beginning any intentional changes to the lake level.

How long will it take to refill the lake?

There is no set time period. The duration of the refill period and the time needed to return to normal lake levels and normal operating guide will be based on many factors, including results of our ongoing observations, the amount of rainfall that occurs during the refill period, the time of year the wall is completed and the normal operating guide for that time of year. As always, safety will remain our top priority during the refill.

Is there a chance the lake could come up before the construction project is completed?

For safety purposes the lake levels will remain at lower levels during construction. However, project engineers will evaluate the potential of raising the water, if possible, through the course of the project. Interim fluctuations of the lake level as much as 5 to 10 feet above the current pool level may occur to facilitate future evaluations of the dam remediation. These fluctuations will be communicated to stakeholders a minimum of 60 days prior to any changes in lake levels.

How much flood damage, on average, does TVA prevent with its management of the river system?

In an average year, TVA prevents about $250 million in flood damage in the TVA region and along the Ohio and Mississippi rivers through the operation of its dams. Overall, TVA has averted more than $7 billion in flood damages.

How were lake levels in summer 2018?  

Above average rainfall this past winter and early spring helped hasten annual spring fill and kept lake levels at or above normal during summer 2018. Both tributary and main Tennessee River lakes have been in good shape in reaching summer lake level targets.

Will TVA refine/update and announce the details of the refill plan with specific dates that provide adequate time to allow for relocation/securing of structures attached to the existing shoreline?

Yes.

Can you provide the independent reports from the Office of the Inspector General, Independent Dam Safety Review Board or the Dam Safety Governance & Oversight?

No, the information is safety sensitive and pre-decisional.

With the grout curtain complete and additional rock applied to both sides of the embankment, in addition to extensive monitoring capability, has TVA considered raising the water level to allow for removal of stranded boats, or to allow for raised levels during the summer months prior to completion of the cutoff wall? 

Yes, future interim fluctuations are being considered with potential elevations to help refine and potentially accelerate the refill plan. Safety of the downstream public remains the top priority of the project.

What is the current hydrostatic pressure on the dam, compared to the increase in pressure from raising the water level by 10 or 20 feet? 

The reservoir currently applies a pressure which is approximately 40 psi greater than that imposed within the river downstream of the dam. This pressure differential increases slightly more than 4 psi for each 10-ft incremental increase in the reservoir elevation.

Will TVA consider leaving the lake at full pool for a longer period (March through December) to allow the Boone Lake community extended usage periods to compensate for the 7 years of lost usage?

No. TVA’s Operating Guide is based on flood prevention. Intentionally exceeding the Operation Guide standards at any reservoir would significantly increase flooding risks on both that reservoir, as well as those downstream.

Will TVA be granting money for Boone Lake Association to clean-up floating debris on the lake as part of the lake refill process?  Will there be any conditions or report requirements placed on the BLA if it accepts TVA Funding?

TVA has provided in-lieu fees to the area but does not place constraints on how those funds are spent by the entities that received them. TVA and project employees volunteer actively in the BLA lake cleanup days.

Will TVA be providing compensation to property owners on the lake due to the long drawdown and loss in property value, as detailed in the 2016 EA?

No.

What is the estimated loss in electric hydro power (kW), and cost to TVA ($) due to loss of hydro power from the reduced water level on Boone Dam (yearly)? 

The drawdown has not reduced the reliability or ability to meet the power needs.

As the estimated cost of the dam repair, $457 million, is ultimately paid through utility rate charges, what initiatives has TVA implemented to save project costs and return some of this money to the rate payers? 

There have not been rate increases due to the project. The project is within TVA’s normal operating budget, which has actually been reduced by $800 million/year since the project began.

Specifically, what would be saved if the completion date is moved from 2022 to 2020? 

The completion date and budget are based on the tasks necessary to build the cutoff wall and ensure safety of the downstream public, safety of the workers and quality of the repair. While we always attempt to complete our work efficiently, the complete date and budget cannot be arbitrarily changed without impacts to one of those commitments and result in an incomplete project.

When will the lake level be raised back up? Is there a chance it could happen before the project is completed?

For safety purposes the lake levels will remain at lower levels during construction. However, project engineers will evaluate the potential of raising the water for assessment purposes through the course of the project.

After the construction is done, how long will it take to bring the lake back up to full summer pool of 1382 feet above sea level?

Even after construction is complete, there will still be testing, monitoring, inspection and other very important work to be done. We will be raising the lake level slowly and looking at it very closely to ensure the seepage and erosion is stopped, the repair is sound, and the embankment is stable after the repair is done. The reservoir fill rate at that time will depend on the data we have gathered during the project, readings from our instruments, and other factors, but we will be proceeding with an abundance of caution. Safety will always be our top priority. 

Topic: Vegetation Management Plan

 

What is the plan for managing vegetation?

TVA is working with local residents, businesses, elected officials, TWRA, and others to address vegetation growth during the Boone Dam Project in a safe, sustainable, and environmentally responsible way.

TVA’s vegetation management plan will emphasize safety, stewardship and a balanced approach, and focus on communicating with homeowners, identifying high-use areas for supplemental vegetation management, utilizing specialized equipment and machinery and creating and implementing a schedule for vegetation work over the next two to three years. 

While the vegetation is beneficial to the natural health of the lake, TVA understands homeowners’ concerns and will work with them during this project to address those concerns. 

Where will you cut vegetation?

TVA will work with the public to identify and manage selected tracts and acreage in the drawdown area, especially high-use areas where vegetation may pose safety or navigational threats. TVA also will make maps and other informational materials available to show areas where work will be done.

In areas near homes, marinas or businesses, TVA will notify and communicate with those homeowners and business owners in advance of vegetation management work. Only vegetation below normal summer pool (1382 feet) will be cut, and our flowage easement extends to the 1390-foot contour.

What will you do with the cut vegetation?

Trees and shrubs also will be shredded and mulched. Large trees will be pruned to a maximum elevation of about five feet below winter pool.

How much will TVA spend on this?

TVA plans to invest more than $2 million in vegetation maintenance at the Boone Dam drawdown area.

What about the environmental concerns?

Environmental Stewardship is a core mission of TVA’s, along with energy and economic development. The vegetation improves water quality, provides aquatic habitat, prevents erosion, and helps create a sustainable shoreline. TWRA requested formally in writing that TVA not cut vegetation unless absolutely necessary for operations or navigation.

What else have you done related to vegetation growth?

TVA also has conducted aerial, boat and land surveys and GIS mapping, formed cross-functional teams to survey, assess and reduce vegetation growth, and also plans to hire a vegetation maintenance liaison to communicate specifically about vegetation management.

TWRA and TVA partnered to plant 400 acres of vegetation on the lake shore, including 12 acres within the Lake Harbor view shed.

TVA has a vegetation work group: we are evaluating next steps.

The online vegetation management brochure for homeowners is: https://www.tva.com/Newsroom/Boone-Dam-Project/Boone-Exposed-Lakebed-An-Owners-Guide

Is TVA going to mow and maintain the areas near my house where weeds, shrubs and other unsightly vegetation is growing?

TVA is looking to provide some shoreline vegetation management assistance for Boone residents on a voluntary basis.

What if I want to plant my own vegetation? What should I plant?

To prevent erosion on the exposed shoreline at Boone, property owners can sow annual rye grass, which tends to germinate quickly, even during cooler fall temperatures and can provide good ground cover through the winter months. You also can choose native plants this spring to beautify your property and hold soil in place. Switchgrass, little bluestem, Indiangrass, cardinal flower, coneflower, sunflower and milkweed are all good low maintenance options and will not create any navigational hazards when water levels return to normal on Boone. More information can be found at the Boone Website.

Can Boone Lake property owners deny individuals the right to cross the dry lake area if the owner owns property rights that extend into the lake to the original stream or river flow area?

The majority of Boone Lake properties (above and below water) are privately owned, and TVA has obtained flowage rights. Unless TVA has reserved rights for the public, crossing private property is generally a civil matter and may involve private trespass issues. Local law enforcement may need to be involved. Property owners should be reminded that, if they decide to use certain measures to prevent trespassing (i.e., signage, fencing, etc.), those measures could become subject to TVA’s Section 26a regulations, which require TVA approval be obtained before any construction or other alterations are carried out that affect navigation, flood control or public lands along the shoreline of TVA lakes or in the Tennessee River or its tributaries.

Has TVA developed a Vegetation Management Plan that includes a specific date and location to start removing lakebed navigation hazards?

Yes, the Supplemental Vegetation Management Plan has been developed with both planned locations and draft schedules. Additional details will be posted on the Boone Project website soon.

Will TVA be reviewing the vegetation removal plan with outside organizations? 

TVA continues to review its supplemental vegetation plan with our longstanding partners at the lake including TWRA, BLA and ETSU (cultural resources).  In addition, TVA continues to accept and review requests from the public for areas to assist with vegetation and areas that the public does not want vegetation management by TVA.

Does TVA plan to remove all lakebed navigation hazards in all channel and cove areas that would be a navigation hazard to boaters, including homeowner property and farmland that extends into the lake?

No, clear cutting is not beneficial for the environment and TVA is not supplementing vegetation management for recreational boating but TVA intends to maintain navigation access while balancing erosion control, wildlife habitat, and long-term fish health for the lake.

How much of the $450 million dollars approved for completing the dam repair is allocated for removal of lakebed vegetation navigation hazards?

None. Efforts, such as maintenance of supplemental vegetation management, come from a different funding source than the repair project. 

Why has TVA not followed through with the 2016 EA plan for "annual and periodic" removal of significant lakebed navigation hazards?  The trees are 30 feet high in many areas. 

The Environmental Assessment assesses potential environmental impacts and was never intended to be a “work plan.” The frequency of the effort was assumed to be worst case scenario to fully capture potential impacts. Limiting the use of mechanical equipment in the lakebed also reduces erosion impacts, which can cause property damage both before and after the lake returns to normal operation.

What navigation hazard removal methods have been determined, and will they include removal or mulching of the debris?

Cutting and mulching will be the primary vegetation management methods and also will help to prevent soil erosion.

Topic: Boone Project Timing

 

Why did it take nine months to come up with a plan?

The situation at Boone is more complicated and complex than we originally thought. To ensure the correct long-term fix, our experts needed time to fully investigate the situation, analyze data and consult with industry experts to determine the right path forward.

How long is this job really going to take?

The project will be completed within the initially projected 5 to 7 year timeframe that was outlined in our July 30, 2015 public meeting.

Why is it taking so long?

TVA came to its estimate that the project would take 5 to 7 years based on several considerations, including the complicated nature of the proposed remediation action and the experiences of other agencies in conducting similar projects. TVA must also account for the safety of its workers when determining how quickly to conduct very complicated construction activities. 

As described in Chapter 2 of the EA, the remediation project requires extensive grouting and the construction of a concrete wall deep into the earthen embankment of the dam. Grouting will require drilling hundreds of separate holes deep into the underlying bedrock. Because the working space atop the earthen embankment is limited, TVA is limited in how many drilling and grouting rigs can work simultaneously. In addition, the construction of a deep, linear wall into the earthen embankment is very complicated; great care must be taken to ensure that the embankment remains stable during construction.   In estimating the timeline, TVA also went through benchmarking of similar seepage remediation projects (including some lasting more than 10 years) that were conducted by other agencies or companies and determined that the proposed project timeline is realistic.

Please also note that TVA’s initial 5- to 7-year estimate included the planning and design period of the project. This period involved extensive investigation to characterize the nature and extent of the seepage issues, consultation and design evaluations with experts in dam safety and engineering, completing numerous environmental and permitting requirements, and mobilization of the resources for construction.  TVA completed this phase of the project within 18 months of its discovery of the seepage at Boone Dam.  For similar projects, planning and design has required at least 3 years.

Topic: Boone Lake Levels

 

Will the water be down for the entire length of the project?

For safety purposes the lake levels will remain at lower levels. However, project engineers will evaluate the potential of raising the water, if possible, through the course of the project for assessment purposes.

How low is the reservoir now?

Boone Reservoir currently operates between 1,350 and 1,355 feet above sea level, and about 10 feet below normal winter pool, though reservoir levels could vary if conditions change.

Why are you keeping it at this elevation?

As a prudent and conservative measure to maximize the safety of those living downstream, TVA has lowered the level of the Boone Reservoir to about 10 feet below normal winter pool elevations, which both reduces the hydrostatic pressure on the components of the dam and reduces the volume of water that would be released in the unlikely event of a dam failure.

What is the real impact to those living downstream of Boone Dam?

If the erosion of the embankment were to continue and the dam were to fail, the impact downstream would be significant.  Homes, businesses and recreational areas would be flooded and thousands of lives would be placed in danger. It is for these reasons that we must maintain lower reservoir levels while we safely correct the seepage problem.

Topic: Boone Project Costs

 

How much will this repair cost?

TVA estimates the project costs up to $457 million.

Who will pay for this?

TVA effectively manages its normal operating budget to provide for such unexpected projects, so there should be no significant impact to ratepayers.

Is this higher than estimated before?

Yes. After the initial two years of work, TVA revised the project cost range estimate from the $200-$300 million range estimated in 2015 to a current range estimate of about  up to $457 million.

Why has the cost estimate increased?

TVA has added detail to the project baseline for activities and re-forecasted estimates to include contingency funds for those activities. These contingencies may or may not occur, so these funds may or may not be used. As a result, the overall funding limit requested by the project has increased.

This increase will help ensure the commitment to return Boone Lake to the community while maintaining the safety of the downstream public. This is normal as the design & construction progresses and will be refined throughout the project.

Other factors impacting the revised cost range estimate include refinements to the project work plan and modifications to maximize quality and safety. Also, the work completed over the past three years has given project engineers better data for estimating costs. As work progresses, those estimates will continue to be refined to narrow the final project completion cost range.

Topic: Community Impacts

 

Is TVA going to buy my house and/or property?

We do not have any plans to purchase property. We are committed to fixing the earthen embankment as quickly and safely as possible.

You bought houses after the Kingston event.  Why won’t you consider buying houses at Boone?

The houses purchased at Kingston were directly damaged by the ash spill or were impacted by the 24/7 heavy equipment activities associated with the remediation.  While we understand that homeowners’ access to Boone Lake will be impacted during the project, there is no physical damage to homes as a result.

Is TVA going to help me get my boat off my lift?

While removal of boats is not something TVA is considering, we will keep the Boone residents and users informed should we significantly fluctuate lake levels. 

I heard you’re helping the marinas financially. Why are you doing something for marina owners and not the boat or homeowners? What about other business owners (restaurants, gas stations) affected by the lack of traffic on the lake?

We recognize that many are impacted by the lower water levels, but marina owners in particular gain their primary income from the lake. We provided other ways to help the community such as new and improved boat ramps for deep water access and a new swim beach.

Will there be other water access areas set up?

We improved or created three access areas: expanding the current boat ramp at Pickens Bridge, installing a new ramp at Devault Bridge with TWRA and created a new swim beach and boat ramp just northeast of the dam on Minga Road.

Will there be local jobs available?

Yes. We anticipate some local sub-contractors and suppliers will be used.  In addition, any contract personnel are likely to take advantage of local hotels, restaurants and stores, creating additional economic activity in the community.

How much does Boone Lake bring to the local economy?

The University of Tennessee recently conducted a study of economic impacts, so we recommend you contact them for additional information visit http://aimag.ag.utk.edu/.

Topic: Involvement of Other Organizations

 

What entity will be the watchdog for TVA’s work here?

The TVA Independent Dam Safety Review Board, consisting of experts in dam safety and operation from across the country, actively monitors the work on Boone Dam, along with TVA Dam Safety Governance & Oversight and the TVA Office of the Inspector General (OIG).

Is EPA involved?

The EPA is not involved.  However, TVA follows the National Environmental Protection Act (NEPA) process which dictates environmental compliance for federal agencies.

Is the Corps of Engineers helping with this work?

The U.S. Army Corps of Engineers has been serving in an advisory role along with other dam owners in the U.S.

What about the quality of the water at Boone? How is that being monitored?

We work with TDEC (Tennessee Department of Environment and Conservation) to monitor water quality.

What will happen to fish habitat?

TVA fisheries biologists are working with TWRA (Tennessee Wildlife Resources Agency) to monitor the fish habitat at Boone. Currently we don’t anticipate any impacts.

Will the work at Boone impact TVA’s nuclear fleet?

No, the work and status at Boone do not impact the safe operation of the TVA nuclear fleet. All three of TVA’s nuclear sites have been evaluated for the flood levels downstream of Boone, and safe operation of the plants has been confirmed. An analysis has been performed that shows any potential flood water from Boone Dam is adequately controlled by Cherokee and other downstream dams.

Topic: Community Updates

 

How will you update the community?

We are committed to keeping the community informed. For monthly updates, sign up for the Boone Update Emails at www.tva.gov/boonedrawdown and follow the project on Twitter @BooneRepair. The project team is also available for speaking engagements. As the project progresses, we will also continue to hold regular meetings to update the community on the status of our work.

Where can the public submit suggestions and feedback?

We review and consider all feedback from the public. The best place is to submit your questions or feedback is the Boone website at www.tva.gov/boonedrawdown.

The Boone Dam Project

TVA has found the fix for seepage at Boone Dam: a composite barrier made of non-erodible material. Construction will take five to seven years. Maximum safety measures for area residents and businesses will remain in place throughout the process. Find out more about what happened at Boone Dam, why and how a team of the country’s finest dam engineers and safety experts arrived at the best possible solution. Click here to read more about the Boone Dam Project.