Coming off a record-breaking wet December, the Savannah River reservoirs received a bit less than average rainfall this January, though conditions are still favorable for runoff.
The Russell sub-basin came very close to receiving average rainfall for the month with a recorded 4.1 inches. That’s 93 percent of normal rainfall for this time of year at Russell.
The Hartwell sub-basin received 70 percent of normal rainfall for the month, recording 3.7 inches. Thurmond received slightly more rain than Hartwell at 79 percent of normal, with a recorded 3.5 inches for the month.
The majority of the month’s rainfall came on Jan. 11 when it rained 2.3 inches at Hartwell, 2.7 inches at Russell and 1.8 inches at Thurmond.
Hartwell began the month at 1.7 feet above summer full pool and peaked on Jan. 20 at 2.7 feet above summer full pool. Our water managers and dam operators have gradually brought the Hartwell pool back down toward winter guide curve level for this time of year, which is about 2.5 feet below summer full pool. As of this writing, Hartwell Lake is 659 feet per mean sea level (ft-msl), or about 1.4 feet above winter guide curve.
Thurmond began the month at 3.2 feet above summer full pool (due to record-breaking December rainfall). Throughout the month, we evacuated the excess flood storage from the Thurmond reservoir and brought the level to winter guide curve. As of this writing, Thurmond Lake is 327.4 ft-msl.
Our goal is to achieve the winter guide curve elevation at both Hartwell and Thurmond so that both reservoirs are on-track for the annual re-fill period. However, the period for the standard 4-foot winter drawdown has already passed, so the target drawdown level should be about 2 feet under summer full pool.
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~Tracy Robillard, public affairs specialist