At last, the signs of spring are all around us. Not only is it “officially” spring, marked by the spring equinox on March 20, but the dogwoods are starting to bud and bloom, the Knoxville Marathon is behind us, and soon the farmer’s markets will be shoulder to shoulder all over town. However, there’s another telltale sign that spring has arrived and it’s the rising water levels of all the lakes and rivers around Knoxville.
Water Levels are on the Rise
While many of us take notice and enjoy the higher water levels that appear in early spring, it might not be common knowledge as to why this happens. For starters, the water levels of the lakes and rivers around Knoxville are controlled by the Tennessee Valley Authority (TVA). TVA is a federally owned corporation that controls the use of 30+ hydroelectric dams which are staggered along the main rivers and their tributaries of the Tennessee Valley region.
The explicit number one goal of TVA’s operations is to control flooding, and they do this with strategically timed releases of water from their dams. The Tennessee Valley is naturally prone to flooding because of the geography of the region and the high amount of precipitation we get each year, especially in the late winter and early spring. To mitigate the natural phenomenon of flooding, TVA collects rain water in its reservoirs (i.e. the lakes above dams, ex. Norris Lake/Norris Dam) and then releases this water at a gradual pace in order to make downstream flows more regular. Releasing water also makes room for more water to collect from the next rain or snow storm. And the cycle continues.
The reason water levels drop dramatically during the late fall and stay low throughout the winter is because TVA is preparing for all the rain and snow and other precipitation that this area receives during the wettest time of year, December – April. Each year around Labor Day TVA starts to release more water from any one particular reservoir than it takes in in order to make the overall water level drop. Then in April, or perhaps even early May, TVA begins to reduce the amount of water it releases from its reservoirs in order to fill up the lakes once again for the enjoyment of boaters and paddle boarders alike. Raising the water level during the late spring and summer is only possible because the risk of flooding during this time of year is substantially lower than in the winter and early spring. Lake levels during the summer can safely remain higher as rainfall and run-off reach their lowest levels for the year.