The work is part of a remedial strategy that saw the construction of a second dam at the site that will secure the reservoir in the face of seismic activity up to the magnitude of the Charleston earthquake, measuring 7.3 on the Richter scale, which struck in 1886.
The level of Lake Murray will now be increased from its current 105m up to the target level of 107m. Once this level is reached, it will be maintained until the last segment of foundation backfilling is completed.
The news was announced by the US Federal Energy Regulatory Commission (FERC), which allowed SCE&G to proceed early with its plans once it saw that the dam was responding well to the construction of the back-up dam. If the dam continues to respond well, refilling at the reservoir will continue to its seasonal level.
The reservoir was first lowered in order to reduce the risks of dam failure during critical stages of construction of the back-up dam.
The programme of work is to be completed by spring 2005.