ENGINEERING PROPOSAL FROM SAVE OUR LAKES NOW FOR INTERIM DROUGHT PLAN UNTIL PLANNED STUDIES ARE COMPLETE

 

PROPOSAL IS BASED ON THE FOLLOWING DATA FROM PREVIOUS DROUGHTS:

1.       Until 2012 the droughts of record had an average annual rainfall of 3600CFS.

2.       A release rate of 3600CFS has been demonstrated to have no significant environmental impact when used for more than 12 consecutive months in the drought of 2008-9.

3.       Based on surveys in 2008-9 downstream water supplies and water quality were adequate during this same period of 3600CFS release rates.

4.       Up to 10ft drop in lake level is acceptable from the stand point of recreation interests but beyond that recreational infrastructure is severely damaged especially when drops in excess of 10ft occur repeatedly over a short span of years.

5.       Power production from the dams of the Savannah River Basin is primarily for peaking power. Consequently it is important from the stand point of power production that the lakes be maintained at as high a level as practical.

6.       The economic impact of low lake levels on power production is far less than the impact of low lake levels on the recreational infrastructure around the lakes especially when the impact on real estate constructed for the purpose of recreation around the lakes is factored in.

7.       The logic behind hydro power is to use existing water from rain as it falls by gravity to the oceans.  Trying to use more water than is provided by rain is illogical. Power production should be balanced against the amount of water available from rain.

8.       Dissolved oxygen levels in the Savannah harbor is controlled primarily from the inflow of water from ocean tides.  And data on dissolved oxygen levels at Clyo show no correlation with release rates from Thurmond down to 3600cfs.

9.       The Corps of Engineers can balance the lakes to within a few tenths of a foot using their current models and knowledge of the hydrology of the Savannah River Basin.

10.   The previous practice of dropping the lakes 4’ at the end of the summer season for flood control was based on having only Lake Thurmond.  Now that Hartwell and Russell collect half the runoff from the basin, a 2’ drop provides the same protection.

PROPOSAL FOR INTERIM DROUGHT PLAN:

Using the hydrology skills available to the Corps of Engineers, balance release rates down to and including 3600cfs to maintain the lakes at as nearly a constant level as practical.  Once the lakes cannot be maintained within 2ft of full pool, drop the release rates to 3600cfs and hold them at this level until the lakes refill.

Other indicators of drought conditions such as flows in the Broad River may be used to initiate low release rates but under no circumstance should the lakes be allowed to drop more than 2’ without initiating minimum release rates.

This proposal balances the whole system from the standpoint of all the corps responsibilities.  Flood control is unaffected.  Hydro power is balanced against the amount of water available.  Recreation is protected from the ravages experienced in recent droughts.  Water quality and supply should be acceptable based on surveys conducted in the drought of 2008-9 when 3600cfs was used for more than 12 consecutive months.  And Fish and Wildlife concerns are balanced against the water available without harming any endangered species.

On the note of impacts to wildlife, it is the opinion of Save Our Lakes Now that the lakes are already doing all that can be reasonably expected to protect against the ravages of droughts.  Prior to constructing Thurmond dam wildlife in the Savannah River was subjected to flows as low as 500cfs in severe droughts compared to the artificial river we have now that never goes below 3600CFS.