Fontana Reservoir

Ecological Health Indicators for
Fontana Reservoir, 2010

Dissolved oxygen

Dissolved oxygen rated good at the forebay and fair at the Little Tennessee mid-reservoir location because a small area along the reservoir bottom contained low dissolved oxygen concentrations (< 2 mg/l) in late summer. A greater area of water with low dissolved oxygen was present at the Tuckasegee location and resulted in a poor rating. In previous years, dissolved oxygen has rated good or fair at the forebay and Little Tennessee mid-reservoir locations and fair or poor at the Tuckasegee location. However, the area with low dissolved oxygen was substantially smaller at the Tuckasegee location in 2004 than in other years, resulting in the only good rating for dissolved oxygen at this location.

Chlorophyll

Chlorophyll rated good at the forebay and Little Tennessee mid-reservoir monitoring locations and fair at the Tuckasegee location. Chlorophyll has rated good at the forebay all years monitored. Chlorophyll ratings have fluctuated between good, fair, and poor at the Little Tennessee mid-reservoir location with no specific trend over time. At the Tuckasegee mid-reservoir location, chlorophyll received good ratings during the early 1990s, but has fluctuated between fair and poor ratings since 1995.

Fish

The fish community rated good at all monitoring locations.  The fish community has rated fair or good at these locations in previous years.

Bottom life

Bottom life rated poor at all monitoring locations. Bottom life has rated poor or at the low end of the fair range at these locations in past years. Each year, relatively few organisms, mainly those capable of tolerating poor conditions, are collected from the reservoir bottom.

Sediment

Sediment quality rated good at the forebay and Tuckasegee mid-reservoir locations because no PCBs or pesticides were detected and all metal concentrations were within the expected range. Copper exceeded expected background levels at the Little Tennessee mid-reservoir location, resulting in a fair rating. In 2008, chromium exceeded suggested background concentrations at this location, but neither copper nor chromium has been above background levels in other monitoring years. Historically, sediment ratings have fluctuated between good and fair at all locations depending on whether or not chlordane was detected. Chlordane was last detected in the reservoir sediments in 2002, and only at the Tuckasegee monitoring location. 

 

See definitions of ecological health indicators and monitoring locations.