Grant helps protect old piece of Sonora-area waterworks

The water for most Tuolumne County residents travels through a wooden flume that clings to mountainsides dense with wildfire fuel.

A $496,000 state grant will help with thinning the trees near the 5,445-foot-long structure, part of a delivery system that dates to the 1850s.

The Sierra Nevada Conservancy, a state agency, awarded the money early this month to the Tuolumne Utilities District. It supplies about 44,000 residents in Twain Harte, Sonora, Columbia, Jamestown and several other locales, along with businesses.

The project will improve forest health and water quality along with protecting the flume, district spokeswoman Lisa Westbrook said. Work on the fuelbreak is scheduled to start in March.

The flume – a metal-lined canal atop wooden supports – is the longest of several along a 15-mile waterway owned by Pacific Gas & Electric Co. downstream of Lyons Reservoir on the Stanislaus River’s south fork. It feeds a small hydropower plant, as well as branch ditches that supply TUD water treatment plants.

Gold Rush pioneers built the original flume system for use in mining. It has been upgraded by PG&E but still is vulnerable to flames, freezing, falling trees and other hazards. TUD warns that fire could put it out of service for more than a month.

The fuel reduction near the flume is part of a larger effort to improve conditions on 733 acres of public and private land in the south fork canyon. Along with TUD and PG&E, the partners are the Stanislaus National Forest; Sierra Pacific Industries, which owns extensive timberland in the county; and the Highway 108 FireSafe Council, which works on forest thinning near towns.

The larger trees will go to the two SPI sawmills in the county, and other excess wood will be chipped and burned to generate electricity.

“The fuel reduction operation will result in biomass energy products and wood products for consumers as well as create jobs in the county which means positive economic benefits, while realizing the benefits and cost avoidance of another catastrophic wildfire,” Mark Luster, community relations manager for the lumber company, said in a news release.

Old flumes continue to serve other water suppliers. The Modesto Irrigation District, for example, has one where its Main Canal crosses Dry Creek near Claus Road.

This story was originally published December 27, 2016 at 2:13 PM with the headline "Grant helps protect old piece of Sonora-area waterworks."