88 percent), 3 rated fair to good (71-73 percent), 3 rated fair (63-68 percent), and 1 rated poor to fair (58 percent). Overall ratings for the 19 tributary reservoirs ranged from 52 to 72 percent (Figure 6). Two reservoirs rated fair to good (both 72 percent), 14 rated fair (58-67 percent), and 3 rated poor to fair (52-56 percent).

Stream monitoring results showed a wide range of ecological conditions among the 12 streams. Three, the Clinch, Powell, and Little Tennessee Rivers, had the highest possible scores for all four ecological health indicators (nutrients, sediment, benthic macroinvertebrates, and fish community). The lowest score (50 percent) was for the French Broad River, where nutrients and fish rated poor, benthos rated fair, and sediments rated good. Scores for the remaining eight streams were evenly distributed within this range.

Most streams and reservoirs had ratings comparable to those observed in 1991 and 1992. Tributary reservoirs had generally poorer ratings than run-of-the-river reservoirs, primarily because of low DO in the hypolimnion. This is an ecologically undesirable condition that is partly due to the strong thermal stratification that occurs in deep reservoirs with relatively long retention times.

Summary

This approach to stream and reservoir monitoring has proved to be a very effective way of tracking water resource conditions throughout the Tennessee Valley. The evaluation procedure focuses on critical indicators of environmental conditions and summarizes results in easily understandable terms. The information that the program produces effectively communicates information to the public and decision makers, and the technical basis for collecting and analyzing data is readily available for those who require more detailed information. TVA distributes about 200 copies of a technical summary report each year in response to requests from other agencies and individuals. The nontechnical report targeted to lake users, property owners, and the general public is mailed to about 12,000 people who have requested it, and another 40,000 copies are distributed through marinas and other public-use areas. The public's response to these products has been overwhelmingly positive.

Each year, TVA critically reviews the results to ensure that the monitoring stations are properly located and that the evaluation scheme yields useful information. As a result of these reviews, several stations have been moved slightly to be more representative of the areas of the reservoirs being sampled, and several refinements have been made of the ecological health-rating criteria. Additional refinements are expected as more information is collected.

One area not addressed by this monitoring and evaluation scheme is the level of satisfaction attained by the people who use TVA lakes and the streams that feed them. Factors such as fishing success, shoreline vistas, ease of access, and degree of solitude experienced greatly affect the aesthetic quality of recreational



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