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and modeling of emergency response alternatives. Not only were emergency managers dependent on the weather forecasts, many local levee districts responsible for maintaining levees in the Sacramento Valley were working to assess downstream levee conditions, and to respond to potential levee threats resulting from the extreme weather and releases from the basin’s reservoirs. Changing weather forecasts were immediately made available to the OICT, who had to quickly modify decisions due to changing weather conditions. Having critical weather, modeling, and water managers in the same location and in close communication with the OICT allowed emergency response alternatives to be developed, assessed, vetted by the management team, and implemented in a timely manner. 5.1.5 Hyatt Powerplant Protection of the Hyatt Powerplant and its connection to the State’s electric power grid was one of the most difficult challenges that faced the DWR OICT. The loss of this facility would have been catastrophic to DWR and the Oroville Emergency Response and Recovery. Releasing sufficient water from the reservoir below the FCO Spillway’s crest (sill) is virtually impossible without the use of Hyatt Powerplant. This would be critical to allow future repairs to the spillway. Secondly, local and State water supplies for agriculture and 25 million people could potentially be severely impacted for years ahead without the use of the Powerplant. There were two main issues associated with Hyatt Powerplant during the emergency: 1) high flows and debris in the tailrace caused backwater effects that limited the functionality of the Powerplant and caused flooding of the Powerplant; and 2) transmission towers, which secured power lines from the Powerplant, were located adjacent to the FCO Spillway chute and were in danger of collapse due to eroding the rock surrounding the two towers and loss of the tower foundations. Due to the high water elevation in the Feather River channel from large spillway releases, compounded by the debris building up in the channel, the Powerplant had to be shut down. DWR OICT, pursuant to the facility Emergency Action Plan, and based upon previous experience during high FCO Spillway release events, were aware of potential damage due to backwater flooding of the Powerplant. Therefore, they immediately implemented a number of emergency mitigation measures. Waterproofing measures were continuously reassessed and additional improvements were made on an ongoing basis. These decisions were part of the daily action planning objectives implemented by the Hyatt Powerplant Operations Strike Team. Over time, additional risks were identified as the water elevation continued to increase on the downstream face of the Powerplant. As responder safety and maintaining waterproofing measures at the Powerplant were extremely critical, additional backup power supplies, pumps, and contract resources were stationed at the Powerplant. Around-the-clock monitoring, reassessment of water elevations, and mitigation measures were reported to the OICT Operations Chief. 54