Comment posted on Yadkin-APGI Reservoir Data website on 2/25/2003
Last weekend, the Yadkin River Basin witnessed precipitation that demonstrates the highly dynamic nature of the River. Significant precipitation covered the entire Basin, resulting in flooding upstream of, and in the upper parts of High Rock Reservoir, where the topography is more riverine than in other areas of the Reservoir. Total streamflow into High Rock Reservoir was above 36,000 cubic feet per second (cfs). [Go to the USGS Website to see the Yadkin River streamflow at Yadkin College.] For comparison purposes, during the drought of 2002, High Rock Reservoir inflows were less than 300 cfs on many days.
During this recent precipitation, APGI generated power and released as much water as possible through its generators but High Rock Reservoir still rose from 8 feet below full pool at midnight on February 21, 2003 to its present level, as noted in the table, below. Flood gates at High Rock Dam were opened at about noon on February 24 to handle additional streamflow, resulting in lost power generation. APGI anticipates spilling through February 26.
Typical draw down of High Rock Reservoir for this time of year is between 12 and 15 feet. This winter, APGI has been operating the Yadkin Project more conservatively to respond to drought conditions. One of the measures taken has been to keep High Rock Reservoir water level higher than typical. This precipitation event demonstrates the highly unpredictable nature of the River and its streamflows.