The reconstructed Oroville Dam reopened on Tuesday, the first time since the spillway split open in February 2017. Water returned to the spillway at 11 a.m. local time, after a 9 a.m. press briefing at the state Department of Water Resources field division office in Oroville, California.
CNN reported that officials decided to reopen the dam to control the rising water in Lake Oroville, one of the state’s key reservoirs.
CNN reported that crews have been working to rebuild the spillway since May 2017, and have since restored its full functionality. Several erosion-reducing measures have been placed including adding a buttress, a concrete “splash pad,” and an underground cutoff wall drilled into deep bedrock.
The Department of Water Resources says it expects to initially be releasing 8,300 cubic feet of water per second, however, the spillway has been rebuilt to handle a flow rate of 270,000 cubic feet of water per second. Crews have also installed temporary cameras and lights along the spillway to monitor water flow.
The Oroville Dam now contains 12.4 million pounds of reinforcing steel, and has an average concrete thickness of 7.5 feet. The repair cost $1.1 billion in total.
According to Chico Enterprise-Record, state officials had high confidence that the spillway would perform successfully after the rebuild.
Source: CNN & Chico Enterprise-Record