Fort
Loudoun Reservoir
Ecological
health rating
The ecological health condition of Fort Loudoun Reservoir rated fair in 2011. Conditions were similar to most previous years. Low ratings for three indicators—chlorophyll, bottom life, and sediment quality—typically reduce the reservoir’s overall health score. In addition, dissolved oxygen has rated poor in some years.
TVA monitors three locations on Fort Loudoun Reservoir—the deep, still water near the dam, called the forebay; the middle part of the reservoir; and the riverlike area at the extreme upper end of a reservoir, called the inflow. Fort Loudoun Reservoir was monitored annually from 1994 through 2007. In 2008, TVA began monitoring Fort Loudoun every other year. (Most TVA reservoirs are monitored every other year.)
Fort
Loudoun Reservoir Ecological Health Ratings, 1994-2011
Click chart for raw
data.
The table below
shows the ratings for individual ecological health indicators at Fort
Loudoun in 2011. These ratings are briefly explained in the paragraphs
that follow.
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Ecological
Health Indicators at
Fort Loudoun Reservoir, 2011
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Monitoring
locations
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Dissolved
oxygen
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Chlorophyll
|
Fish
|
Bottom
life
|
Sediment
|
| Forebay |
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|
|
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| Mid-reservoir |
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|
|
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| Inflow |
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Dissolved oxygen
Dissolved oxygen rated fair at the forebay and good at the mid-reservoir monitoring location. This indicator usually rates good at the mid-reservoir location, but ratings have varied between good, fair, and poor at the forebay, generally in response to reservoir flow conditions. TVA has installed aeration equipment to add oxygen to the deep water above Fort Loudoun Dam and to improve conditions immediately downstream. Learn more about these improvements.
Chlorophyll
Average summer chlorophyll concentrations were high at both monitoring locations, resulting in poor ratings. High chlorophyll concentrations are a consistent issue on Fort Loudoun, rating poor at both sites in most previous years.
Fish
The fish assemblage rated “high fair” at all three monitoring locations. The variety of fish collected at each location was good, but catch rates were slightly lower than desired and composition was dominated by a few species such as gizzard shad, bluegill, and/or largemouth bass. The fish community typically scores good or at the upper end of the fair range at the forebay and mid-reservoir, while scores at the inflow have generally fluctuated within the fair range.
Bottom life
Similar to previous years, bottom life rated poor at the forebay and inflow monitoring locations and fair at the mid-reservoir location. Relatively few organisms are usually collected from the forebay and inflow locations, and those collected are primarily species capable of tolerating poor conditions. Bottom life at the mid-reservoir location typically rates fair due to greater diversity, which includes a better representation of intolerant species such as mayflies.
Sediment
Sediment quality rated fair at both the forebay and mid-reservoir monitoring locations because PCBs were detected. Sediment quality typically rates fair at both locations due to chlordane, PCBs, and/or zinc exceeding suggested limits.
See definitions of
ecological health indicators and monitoring locations.
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Fish
consumption advisories
Fort Loudoun Reservoir - TVA maintains a program to examine contaminants in fish fillets from TVA reservoirs and their major tributary streams on a rotational basis. The data collected from this program is distributed to the state officials who are responsible for placing or removing fish tissue consumption advisories on those bodies of water. For information on advisories currently in effect for Fort Loudoun Reservoir, visit the Water Quality Division of Tennessee Department of Environment & Conservation’s web page. http://www.tn.gov/environment/water.shtml.
Tennessee Valley Authority
