The details of controlling lake levels to suit both downstream and upstream users of the lake can appear complicated. But it is really quite simple. To illustrate let me use the analogy of maintaining a bank account to take care of a charity. Assume that the charity needs $3,600/month to meet it's needs. Let's further assume that the only contributor to this charity is putting an average of $3,600/month into the account.
Given this scenario, if the charity takes out more than $3,600/mo the bank account will eventually go dry and the charity will no longer be able to meet it's needs. But if the charity takes out only $3,600/mo the bank account will remain solvent and the charity will be able to meet it's needs.
The downstream users along the Savannah River below the Thurmond Dam are like the charity. The upstream users are like the person contributing to the charity. They are contributing by allowing water to flow through the dam according to the Corps' drought plan. If the Corps limits the water through the dam to the average amount coming in each month it is to the benefit of the downstream users. It is not true that such controls are only for the benefit of the people around the lake. Such measures protect those downstream from a catastrophic failure with the lakes going dry and the Corps no longer being able to supply their needs.
It turns out that a flow rate of 3,600cfs through the dam equals the monthly average of rain coming into the lake during the recent drought which is the worst drought we have experienced since the dam was built. And we have fully demonstrated that a flow of 3,600cfs meets the needs of everyone downstream such as Augusta for water quality, industry along the river, and environmental concerns. Hence all we are asking is for the Corps to change their drought plan such that we no longer send more than 3600cfs downstream anytime the lakes drop by as much as 2ft. The reason for starting at 2ft below full is that month to month variations can allow the lake to drop 6ft so starting at 2ft below full limits the total drop to an acceptable 8ft.
The only other concerns I have heard from the Corps are lost power generation and the need for occasional high flows down the river to flush pockets of pollutants in a fashion similar to flooding from a rain. So far as power generation, we've talked with representatives of SEPA and they tell us that Lake Thurmond is part of a 10 lake grid and any loss in power production at Thurmond can be made up by increased production within this grid at lakes not suffering the same drought. Besides, purchase of power outside this grid if needed is not nearly as expensive as the costs that are encountered whenever the lakes drop more than 10 feet. So far as occasional high flows down the river, 3600cfs is an average and can include much higher flows from time to time as long as the overall monthly or weekly average is 3600. Such spikes in flow can even be matched with times when it rains to give extremely high flows in the river.
Other measures to minimize day to day fluctuations are desirable but the restriction of 3,600cfs anytime the lakes drop 2ft takes care of the major problems of past droughts. For example operators at the dam have detailed information showing when rains swell streams below the dam. This information could be used when the lake is down to increase water retention above the dam when 3,600cfs is no longer needed downstream. And testing lower flows such as 3100cfs could also help minimize level fluctuations during droughts. And rethinking water diversion rates for the Augusta Canal could also help at times of droughts. But all these complicate the issue and can be ignored until the drought plan is modified.
It is extremely important that the Corps discontinue the past drought plan which has failed numerous times and adopt this recommendation as soon as possible. Unless and until they do the lack of confidence in having suitable lake levels is destroying prospects for future business and real estate activities around the lakes, and recreational events such as national fishing tournaments. This lack of confidence is devastating the economics attributed to the lakes for cities like Lincolnton, McCormick, and Anderson.
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