Not much has changed since the last time except that inflows have continued to decline as have lake elevations. June concluded with 72% of its long term average and here at the end of July, we’ve only had 67% of long term average rainfall amounts. That puts us at 62% of LTA year to date. Lake James, Norman, and Wylie have dropped significantly. Currently James is 1.74 ft. below target and 1.26 ft. above normal minimum. Jocassee is 14 ft below target and 11.40 ft above minimum level.
The main factor driving the C/W operations during these times is release for industrial and environmental support. Since the first week of July, we have released over 32,000 ac.-ft. of water from the combined storage volumes of Norman, James, and Wylie with an inflow of approximately only 3,800 ac.-ft. For each 100 ac.-ft. released, 90 ac.-ft. comes out of storage. Between current levels and normal minimum levels, we have only 58,000 ac.-ft. remaining to minimum lake levels. Without some rainfall events, we will be at normal minimums in late September. Current inflows into Lake James are about 50 MWh per day. Thunderstorms this past week raised the levels at Bridgewater, so we increased our generation a bit to share this water with Lake Norman. Currently there is ~200 cfs average flow in the South Fork of the Catawba. That’s approximately 50 MWh of inflow into Wylie each day ( 200cfs *24hrs * 1.9 /191 = 47.7Mwh) . Our Wylie discharge has been 150 MWh per day leaving Cowan’s Ford/ Bridgewater to supply the remainder. Cowans Ford has been running 60 to 80 per day and so Norman and Wylie are both dropping. In the Nantahala West area, the Nantahala stream feeding Nantahala Lake is below average, representing almost 6 hours of daily generation at 40 MW, so we’re losing level in Nantahala Lake as well. The all time minimum flow for this date was 43cfs in 1986. Today we are at 67cfs. The Savannah river basin (Jocassee, Keowee) remains the driest area on the system as flows continue to be well below average.
