A fire started at the 14.1-MW Philpott hydro plant about 6:50 pm on March 29 but has been extinguished.
The fire began in the upper level of the powerhouse basement, where the control room is located, says Rocky Rockwell, operations project manager for Philpott Lake.
This dam and hydro powerhouse, operated by the U.S. Army Corps of Engineers, is located on the Smith River in Virginia. The dam is 920 feet long and 220 feet high and the powerhouse contains three Francis turbine-generator units.
The facility is undergoing life extension and electrical modernization work, with Eaton as the contractor. Some of the existing components date back to when the plant was commissioned, in 1953.
The Corps says the Philpott facility is remotely controlled from its John H. Kerr facility. All personnel had exited the powerhouse before the smoke alarm sounded. Initial investigations indicate an existing 52D switch exploded about 15 minutes after the second generating unit came on line.
Rockwell says the substantial majority of the damage appears to be to the switchgear systems that are being replaced. Eaton personnel are in the process of erecting a new switchgear building outside the powerhouse. “We were probably three weeks away from installing the new switchgear and beginning the process of moving everything over to the new system,” Rockwell says. The Corps says there appears to be no connection between the failure and the new construction work under way.
The Corps provided an initial damage estimate of $2 million to $3 million to the fire chief but says that the equipment will not need to be replaced in kind because of the new system being installed. Expenses primarily will be related to the cost of cleanup.
The Corps is currently performing a more thorough assessment of the situation. This will include determining if arc flash was involved.