By MIKE JENSEN
A boulder rolled down the South Fork Stanislaus River canyon overnight, damaging PG&Es water flume, resulting in the water supply being shut off for most of Tuolumne County.
The boulder broke a support beam under the flume on the main canal about three-quarters of a mile below Lyons Reservoir.
The canal and flume supply water to Tuolumne Utilities District as well as numerous customers who take their water directly from the open ditches flowing throughout the county.
It will likely take two or three days to repair the flume, according to PG&E Supervisor Scott Fee.
Fee said an alarm alerted PG&E of low water flow and a PG&E worker discovered the damaged flume about 1 a.m. today.
All water users are urged to conserve. Yard watering and car washing should be curtailed throughout the outage.
TUD should be able to keep water flowing with its wells and its stored water until the flume is repaired, said TUD secretary Karla Hoback.
Its not a major emergency, she said. We just want to make sure that if we go beyond the three days, we have enough water to carry us through.
TUDs engineers and general manager were unavailable for comment this morning.
PG&Es Fee said this morning that the mile-long flume was not broken but is sagging where the boulder hit and broke loose a six-inch by six-inch support beam.
Water will have to be shut off while the flume is repaired.
Reconstruction was expected to begin this morning and the needed materials are already in stock, Fee said. The material will be flown in with helicopters.
I dont think theres going to be a problem, he said.