The July 8 Balancing the Basin purports to explain the Corps' thinking when it comes to determining outflows from Lake Thurmond which in turn dictates the level of both Thurmond and Hartwell. The initial reasoning offers the thought that normal is not full pool. Rather normal is what the average levels have been over the years.
I have a huge problem with this concept. Normal or average led to devastating loss of lake level 3 times in the last decade. To call this acceptable is ludicrous. Why would we want to repeat those conditions where recreation was destroyed and the Corps was placed in a dire situation where they had little to no control over their various other responsibilities.
It is obvious to me as an engineer why the Corps lost control of the lakes. It should be equally obvious to the Corps but for some reason they continue to go headlong into situations where the lakes can not recover should a drought occur. We have been pleading with the Corps to hold lake levels as near as possible to full pool until the fall and winter by reducing release rates from Thurmond to as low as 3600cfs when needed. The Corps has shown they can hold lake levels to within 6" of their targeted level except in extreme conditions such as rainfall that yields less than 3600cfs inflow. The reason for choosing 3600cfs as the low point is we have demonstrated repeatedly in past droughts that this flow does not significantly impact the environment or water supply needs.
It can be argued that higher flows to the river are better but that's like the argument that you want to buy more than your income will allow. It feels good for awhile but becomes totally destructive to all concerned whether upstream or downstream when levels drop more than 10ft.
Additionally we have pleaded with the Corps for several years to reduce the fall/winter drawdown to 2' instead of 4'. This again is so we enter any drought, should one occur, at as full a lake level as possible. The reason for choosing 2' is that volume of water, counting all 3 lakes, has been demonstrated since Thurmond was first built to handle the heavy fall and winter runoffs. A 2' change now with 3 lakes involved is the same as the 4' drop used prior to building Hartwell and Russell.
The explanation for what determines release rates while the lakes are within 4' of full was inflow volumes, hydropower, and environmental and municipal demands. What is missing is the observation that none of these can be managed well when the lakes drop drastically. The reason this occurred in recent droughts is we entered the drought with lake levels already down 4' and even then we did not decrease release rates enough to counter the drought. And there is also no mention of the fact that recreation (another of the Corps' responsibilities) was virtually destroyed from recent droughts.
The discussion in the article also goes into some detail about power needs. Ironically the Corps refuses to acknowledge economic impact of low lake levels on real estate and the recreational infrastructure around the lakes. But when power generation is discussed it is purely an economic discussion because there is more than adequate power available elsewhere on the grid. The total value of power generated from our lakes is no match for the losses to real estate and recreation when lake levels drop more than 10ft.
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