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TVA Erosion Control: Inch-by-Inch11-01-03 | News



TVA Erosion Control: Inch-by-Inch

By Sean Stowell






Tree revetments were used in some areas along with livestock exclusion fencing. The shoreline buffer included native alder, silky dogwood, buttonbush and American sycamore. Their deep root systems bind and hold soil in place.


There was good news and bad news during the Tennessee Valley Authority?EUR??,,????'???s Shoreline Conditions Assessment and Cooperative Stabilization Projects. The good news was only eight percent of the 11,000 mile shoreline was found to be in poor condition. The bad news was that eight percent equates to nearly 900 miles.

With 11,000 miles of shoreline around 34 TVA reservoirs in seven states, Jack Muncy, a certified professional in erosion and sediment control and TVA forester, had his erosion control team inspect the shoreline inch-by-inch?EUR??,,????'??+floating the entire reservoir system by boat.

History of TVA

According to TVA?EUR??,,????'???s Web site, president Franklin D. Roosevelt envisioned TVA as a totally different kind of agency. He asked Congress to create ?EUR??,,????'??a corporation clothed with the power of government but possessed of the flexibility and initiative of a private enterprise.?EUR??,,????'?? On May 18, 1933, Congress passed the TVA Act.






This site on Fort Patrick Henry Reservoir was treated with the assistance of Warriors?EUR??,,????'??? Path State Park employees and inmate labor from the Tennessee Department of Corrections.


Even by Depression standards, the Tennessee Valley was in sad shape in 1933. Much of the land had been farmed too hard for too long, eroding and depleting the soil. Crop yields had fallen along with farm incomes. The best timber had been cut. TVA developed fertilizers, taught farmers how to improve crop yields, and helped replant forests, control forest fires, and improve habitat for wildlife and fish. The most dramatic change in Valley life came from the electricity generated by TVA dams. Electric lights and modern appliances made life easier and farms more productive.






The Chatuge Reservoir (NC) shoreline before treatment. See pg. 56 for what the Chatuge Reservoir looks like two years after treatment.


During World War II, the United States needed aluminum to build bombs and airplanes, and aluminum plants required electricity. To provide power for such critical war industries, TVA engaged in one of the largest hydropower construction programs ever undertaken in the United States. Early in 1942, when the effort reached its peak, 12 hydroelectric projects and a steam plant were under construction at the same time, and design and construction employment reached 28,000.

By the end of the war, TVA had completed a 650-mile navigation channel the length of the Tennessee River and had become the nation?EUR??,,????'???s largest electricity supplier. Even so, the demand for electricity was outstripping TVA?EUR??,,????'???s capacity to produce power from hydroelectric dams. Political interference kept TVA from securing additional federal appropriations to build coal-fired plants, so it sought the authority to issue bonds. Congress passed legislation in 1959 to make the TVA power system self-financing, and from that point on it would pay its own way.




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A field assessment worker shows the number of feet of critically eroding shoreline before treatment on Tellico Reservoir (TN).


In the late 1990s the electric-utility industry moved toward restructuring, TVA began preparing for competition. It cut operating costs by nearly $800 million a year, reduced its workforce by more than half, increased the generating capacity of its plants, stopped building nuclear plants, and developed a plan to meet the energy needs of the Tennessee Valley through the year 2020.

TVA has plants in seven states (Tennessee, Kentucky, Virginia, North Carolina, Georgia, Alabama, and Mississippi). It is the largest public power company in America with 30,365 megawatts of generating capacity.

The Project

Muncy describes the project as twofold: assessment and stabilization. The shoreline stabilization project began in 1994 and by 1997 Muncy and his team had assessed 6,000 miles of reservoir shoreline. Last year the remaining 5,000 miles were completed, giving TVA the first complete picture of shoreline conditions.






The same shoreline on Tellico two years after soil bioengineering.


?EUR??,,????'??We made an assessment of the resource and looked at the shoreline,?EUR??,,????'?? Muncy said. ?EUR??,,????'??We categorized the shoreline areas as good, fair, or poor to understand the magnitude of the shoreline erosion and the factors that impacted the erosion.?EUR??,,????'??

On most TVA reservoirs the dominant type of vegetation, trees, shrubs or grass, and the dominant land use such as residential, industrial or agriculture, plus impacts to the vegetation such as livestock, grazing, clearing or mowing and the general soil erosion rate is now known. TVA believes this to be the first comprehensive, holistic large-scale field assessment of reservoir shoreline erosion and the factors that contribute to it.






Several agencies have helped fund or provided labor for the shoreline restoration project. Workshops were also conducted to help transfer practical information to private shoreline construction contractors, lakefront property owners and others.


The solution was rather simple. TVA used native plants suited to each particular site. The agency works to keep the soil around reservoirs in place by constructing conservation buffers, which are 50-foot wide strips of land that remain in permanent vegetation. Scenic beauty and enhanced wildlife habitats are added benefits of these buffers. Between 1996 and this year, TVA helped stabilize 250 critically eroding sites along 45 miles of shoreline throughout the watershed.

?EUR??,,????'??In 1997 we became very action oriented,?EUR??,,????'?? Muncy said. ?EUR??,,????'??We started targeting specific sites. We only worked on the areas that were in the poor category. The good and fair areas received no treatment.?EUR??,,????'??

Taking corrective action is the real point of the shoreline assessment. TVA is using the data to assess how best to use its limited resources to minimize and manage the public shoreline for the greatest public benefit. Between 1992 and 1996, TVA erosion control specialists installed practical on-the-ground demonstrations of various cost-effective soil erosion control treatments prior to development and implementation of a valley-wide action program. The pilot demonstration work was conducted at 15 critically eroding sites at five different reservoirs and covered seven shoreline miles.






Rock-filled gabions, cooperatively constructed with the Johnson City, Tenn., Parks and Recreation Dept., are the main erosion control features along the Boone Reservoir shoreline.


Cooperators have provided about 40 cents of each dollar invested in this soil erosion control work. TVA?EUR??,,????'???s goal is to stabilize all critically eroding shoreline sites throughout TVA?EUR??,,????'???s multistate reservoir systems through partnership efforts. TVA and cooperators use several innovative, practical, and cost-effective techniques to mitigate shoreline erosion.

?EUR??,,????'??The challenge was coming up with a practical approach to characterize this project,?EUR??,,????'?? Muncy said. ?EUR??,,????'??Two interns and I came up with an approach on a pilot basis and then the watershed teams did the entire 11,000 miles.

?EUR??,,????'??What we did was a field assessment. We wanted facts to present to management.?EUR??,,????'??

According to Muncy, the project stressed grasses and trees combined with structures such as rock rip-rap, gabion buckets or coir rolls.






Starting in 1992, and parallel with the ongoing field assessment, practical on-the-ground demonstrations of various cost-effective soil erosion control treatments were installed at 15 critically-eroding sites at five different reservoirs covering seven shoreline miles. The top photo shows an eroding shoreline on Melton Hill Reservoir (TN) impacted by livestock.


The TVA shoreline conditions assessment and cooperative stabilization project earned the 2003 Environmental Achievement Award of Distinction from the International Erosion Control Association.

In the Spirit of Cooperation

This project also demonstrated cooperation between TVA and several other state and county agencies within the TVA?EUR??,,????'???s service area.

?EUR??,,????'??Because of the level of support from project cooperators, we were able to stretch limited funding to attain greater results overall,?EUR??,,????'?? Muncy said. ?EUR??,,????'??The cooperators support was a key factor in the success of the overall project.?EUR??,,????'??






Two years after establishing a shoreline management buffer which included livestock exclusion and watering lane fencing, as well as hand planted native bare root woody shrubs and trees, the Melton Hill Reservoir shoreline is both stable and healthy.


Assisting on the project were county parks authorities who had land within the TVA territory, various highway departments, state departments of environment and conservation, and even inmate labor. According to Muncy, TVA would identify sites and work with these governmental bodies to see which pieces of the puzzle each one could fill.

?EUR??,,????'??I?EUR??,,????'???ve used quite a bit of inmate labor especially in southwest Virginia and upper-east Tennessee,?EUR??,,????'?? he said. ?EUR??,,????'??The Tennessee Department of Corrections and the local sheriff?EUR??,,????'???s departments have all provided inmate labor. That really helps to stretch your dollars when we can get inmate labor.?EUR??,,????'??






Here is the shoreline on Chatuge two years after soil bioengineering treatment with coir fascine rolls, native woody brush layers, and rock riprap toe protection.


While Muncy could have assessed the entire shoreline by helicopter in a fraction of the time it took him to do it by boat, the results would have been remarkably different.

?EUR??,,????'??The helicopter would have given us just a general view,?EUR??,,????'?? he said. ?EUR??,,????'??We wanted to be able to characterize the shoreline and paint a true picture of what was going on.?EUR??,,????'??

To inform waterfront landowners about shoreline soil conservation, the agency has developed a booklet and CD-ROM called ?EUR??,,????'??Banks and Buffers.?EUR??,,????'?? The package helps users select native plants that are right for specific needs, preferences, and site conditions. It also includes information on where to get the plants, how to grow them, and what aesthetic, economic, or wildlife-related value they have.






TVA adopted a residential Shoreline Management Policy in which residential access on TVA land is limited to areas where private access rights currently exist.


Besides being a delicate point where water, erosion, and pollution runoff met, shorelines are also prime recreation and land development spots. To protect natural resources while allowing reasonable access to the water, TVA adopted a residential Shoreline Management Policy in 1999. According to a TVA annual environmental report, under the new policy, residential access on TVA land is limited to areas where private-access rights currently exist (about 38 percent of the shorelines). A ?EUR??,,????'??maintain and gain?EUR??,,????'?? strategy lets land owners request permission to trade access rights?EUR??,,????'??+giving up one location for another.

TVA will continue to evaluate requests for building activities and review them to gauge their potential environmental impact. To ensure that future land development will be compatible with environmental-protection goals, the policy also includes new standards for docks and erosion control, and requires a buffer zone for newly developed residential areas that border TVA public land.






Almost 900 miles of the reservoir shoreline assessed in the field was in poor condition such as above; 23 percent in fair condition, and 69 percent in good condition.


Shaped by extensive public input, the new policy seeks to balance shoreline development and recreational use issues with resource-conservation needs to keep some of the most sensitive ecosystems in the Tennessee River watershed from eroding away.

In all seven of these states, hundreds have helped restore an area vital to one of this country?EUR??,,????'???s largest public utilities, while saving an environmentally important region.


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