U.S. Army Corps of Engineers
Nashville Dist.
Rivers And Our Natural Heritage
Tennessee covers ten distinctly different regions and is blessed with tremendous landscape diversity. Each region, called a physiographic province, has its own characteristics and directly affects not only the way in which we live on the land, but also the natural and historical heritage associated with it. From the Blue Ridge Mountains to the Mississippi River, our natural and cultural heritage, as well as the way in which we live today, is forever tied to the landscape.
Across this landscape flow more than fifteen thousand miles of rivers. These rivers are home to a rich and diverse natural heritage, including the most diverse collection of freshwater animals of any state. Tennessee is home to over three hundred species of fish, and the Ohio River Basin-containing most of our state-has the world's richest assemblage of freshwater mussels. The landscape through which our rivers flow contains more species of trees than all of Europe. These rivers also support a rich cultural heritage, with important archaeological and historical sites along many of their banks. Communities, recognizing the importance of rivers to the quality of life, are developing greenways along river banks. Throughout the state, we are drawn to our rivers for fishing, swimming, boating, commerce, wildlife viewing and simply to escape the pressures of day-to-day life.
As the people of Tennessee continue to enjoy strong economic growth, increasing demands and threats are placed upon our river systems. These threats directly affect the natural and historical heritage of our rivers, and-ultimately-public health and quality of life. Threats are varied and include pollution and other impacts from many sources: residential, construction, municipal and commercial stormwater runoff, agricultural runoff (containing sediments, pesticides, herbicides and fertilizers), impoundments, deforestation of streambanks, channel alteration and exotic species.
These increased pressures on our natural systems often result in losses of natural and historical resources. For example, nearly half of the Ohio River Basin's once diverse freshwater mussel species are either extinct or endangered. Nearly 30 percent of the Basin's fish species are considered rare, with nine species presumed extinct in Tennessee. One quarter of our amphibian species, which spend much of their life cycle in water, are considered rare. Indeed, Tennessee has more federally-listed endangered species than forty-six other states and, along with three other states, has the highest percentage of aquatic species at risk. Ten percent of our river miles do not meet their designated uses, and 110 miles of rivers are posted against human contact. A full 20 percent of the Tennessee River system is impounded, and most of the rivers of west Tennessee have been channelized into straight line drainage ditches. Both of these latter activities have resulted in enormous habitat loss, with channelization resulting in loss of recreational opportunities as well. Impoundments have permanently flooded important historical and ecological resources.
A 1995 report by the National Biological Service entitled Endangered Ecosystems of the United States found that streams of the Mississippi Alluvial Plain in west Tennessee were critically endangered, aquatic mussel beds in Tennessee were endangered, and riparian and southern bottomland hardwood forests were threatened throughout their range. A 1995 report by Defenders of Wildlife entitled Endangered Ecosystems found that Tennessee has the fifth highest overall risk to ecosystems with six of the twenty-one ecosystems identified as endangered, including large streams and rivers as well as forested wetlands. Specifically, the report identified a 60 percent loss of bottomland hardwood forests, a 60-75 percent loss of cypress-tupelo forest in west Tennessee, a 59 percent loss of wetlands and a greater than 90 percent loss of aquatic mussel beds.
Much progress is being made to restore degraded rivers and to protect those that are yet intact. Across the state, local communities and organizations are working with state and federal agencies to find ways to protect our rivers without adversely impacting continued economic growth.
In one way or another, we are all directly connected to these rivers through uses ranging from drinking water supply to agriculture, recreation to transportation, even as a source of food. How well are we caring for our rivers, and how do our actions affect others downstream? To help answer these and other such questions, this report gathers both qualitative and quantitative information about the status and condition of our rivers for use by resource managers, planners, citizens and others. We hope that this report, and its associated technical data, will be another important tool to help guide our way through Tennessee's rapid growth in a way that protects our natural and historical heritage and ensures clean, functional rivers for generations yet to come.
Reggie Reeves, Director
TDEC/Division of Natural Heritage
