Kentucky Reservoir

The ecological health of Kentucky Reservoir scored at the upper end of the fair range in 2011. Kentucky rated good all other years except 1995 and 2009, when the rating was at the upper end of the fair range.

TVA monitors four locations on Kentucky Reservoir—the deep, still water near the dam, called the forebay; the middle part of the reservoir; the Big Sandy embayment; and the riverlike area at the extreme upper end of the reservoir, called the inflow—usually on a two-year cycle.

Ecological Health Indicators at Kentucky Reservoir — 2011

Monitoring location Dissolved
Chlorophyll Fish Bottom

Forebay Fair Poor Good Good Fair
Mid-reservoir Fair Fair Good Good Fair
Big Sandy embayment Poor Poor Fair Poor Fair
Inflow     Good Fair  

Dissolved oxygen

Dissolved oxygen rated fair at the forebay and mid-reservoir, and poor at the Big Sandy embayment location. Dissolved oxygen ratings were reduced at all three locations because concentrations were low along the reservoir bottom during June and/or July. A larger portion of the reservoir bottom was exposed to low concentrations in the Big Sandy embayment, resulting in a lower rating. This indicator rated good at the mid-reservoir all other years, but ratings have varied between good and fair at the forebay and good, fair and poor at the embayment location, generally in response to reservoir flow conditions.  


As in previous years, average summer chlorophyll concentrations were relatively high at the forebay and Big Sandy embayment monitoring locations, rating poor. Concentrations at the mid-reservoir location were slightly elevated, resulting in a fair rating. Chlorophyll has rated good at the mid-reservoir location all other years except 2001 and 2009, when the indicator also received a fair rating. 


The fish community rated good at the three monitoring locations in the main body of the reservoir, and “high fair” at the Big Sandy embayment location. Ratings for the fish community have varied between fair and good at all locations, with more frequent “high fair” or good ratings in recent years.

Bottom life

Monitoring results for bottom life were generally similar to previous years. The forebay and mid-reservoir locations rated good, the inflow rated “high fair” and the Big Sandy embayment rated poor. The embayment received a lower score because of the higher proportion of tolerant organisms and lower overall diversity, a likely result of the poor dissolved oxygen conditions that developed at this location.


Sediment quality rated fair at the three locations sampled. Low levels of PCBs were detected in samples from each location, and arsenic was slightly elevated in the Big Sandy Embayment sample. Sediment quality has rated good in Kentucky Reservoir all other years except 1999 and 2001, when it also rated fair at the Big Sandy embayment due to elevated concentrations of arsenic.

Fish consumption advisories

Kentucky 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 Kentucky Reservoir, visit the Kentucky Departments of Fish and Wildlife Resources Web page