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Fort Patrick Henry Reservoir

Ecological health rating

Fort Patrick Henry Reservoir rated poor in 2011. Fort Patrick Henry has received a fair or poor rating every year except 2003, when it rated good due primarily to improved chlorophyll levels (see discussion below).

TVA monitors one location on Fort Patrick Henry Reservoir—the deep, still water near the dam, called the forebay—usually on a two-year cycle.

Fort Patrick Henry Reservoir Ecological Health Ratings, 1994-2011

rating chart

Click chart for raw data.  


The table below shows the ratings for individual ecological health indicators at Fort Patrick Henry in 2011. These ratings are briefly explained in the paragraphs that follow.

Ecological Health Indicators at
Fort Patrick Henry Reservoir, 2011


Dissolved oxygen



Bottom life



Dissolved oxygen

Dissolved oxygen rated good, as in previous years. The reservoir’s small size and short residence time (the length of time the water sits in the reservoir) inhibits it from becoming thermally stratified and from developing low dissolved oxygen levels (less than two milligrams per liter) during the summer.


As in previous years, chlorophyll concentrations were elevated throughout most of the summer and autumn and rated poor. The exception was in 2003 when a shorter average residence time limited algae growth, resulting in the only good rating for this indicator.


The fish community rated fair. This indicator typically rates poor or fair. Monitoring consistently reveals a lower-than-expected number of species and a high proportion of tolerant individuals, such as gizzard shad.

Bottom life

Bottom life rated fair because a low variety of animals were found in samples collected from the reservoir bottom and most were species able to tolerate poor conditions.  Bottom life typically rates within the fair range or at the upper end of the poor range.


Sediment quality rated fair because samples contained PCBs and the concentration of arsenic was slightly above suggested background levels. Sediment quality typically rates fair due to low levels of chlordane, a pesticide previously used to control termites and crop pests, and/or copper exceeding suggested background levels. PCBs were last detected in 1994.


See definitions of ecological health indicators and monitoring locations.


Fish consumption advisories

Fort Patrick Henry 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 Patrick Henry Reservoir, visit the Water Quality Division of Tennessee Department of Environment & Conservation’s web page.



lake photo

Fort Patrick Henry Reservoir is located in Sullivan County in the northeastern corner of Tennessee.


More about Fort Patrick Henry

Sport fishing ratings

General information

To see monitoring results for other TVA reservoirs, choose from the list below.


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