Groups seek to restore local watersheds | SierraSun.com

Groups seek to restore local watersheds

Andrew Cristancho
Sierra Sun

Andrew Cristancho/Sierra SunOn the trail leading up to Emigrant Canyon, Jeff Brown of Sagehen Creek Field Station explains the history of local geology with the aiid of a soon-to-be-published digital map of the area.

On a tour Wednesday through Billy Mack Canyon above the west end of Donner Lake, Truckee Land Trust’s Sarah Taddo stopped and dug into a pile of sand that she estimated was 6-feet deep.

The sand had once been spread on Interstate 80 to give cars better traction, but for decades washed down into the canyon.

The 600-acre Billy Mack watershed might have absorbed the road debris were it not for Old Highway 37, an eroding cattle and logging road once used to transport such resources as granite and lumber from the surrounding hills. Old roads like it funnel water and eroded material directly into Donner Lake.

“There’s a pile of road sand that creates a dead zone at the west end of Donner Lake,” said John Eaton of the Mountain Area Preservation Foundation.

Eaton and Taddo were part of a group of environmentalists who toured Billy Mack, Emigrant and Coldstream canyons Tuesday to assess the damage from decades of human development and logging activity.

Left alone, canyons are places where meadows flourish, providing a natural filtration system that prevents sediment from reaching a body of water like Donner Lake. But since the mid-1800s, the canyonlands around Truckee have experienced significant human impact and environmental degradation.

Recommended Stories For You

“A hundred and fifty years of resource extraction and road building went on in these areas,” said Executive Director Lisa Wallace of the Truckee River Watershed Council. “Many of the roads went in when we didn’t pay attention to how roads were built.”

Wallace went on to explain that old dirt roads cause erosion, which in turn destroys wildlife habitat.

“Donner Lake has incredible aesthetic value; it’s undergone intense development and it hasn’t received a lot of restoration,” Wallace said.

This makes Donner Lake and the surrounding watersheds important to Wallace’s agency.

“Donner Lake is a high priority because of its aesthetic value, its water supply and its wildlife habitat,” she said.

Emigrant and Billy Mack canyons rise above the west end of Donner Lake in Truckee and are crisscrossed with 150 years’ worth of logging and cattle road cuts and railroad activity.

The Truckee Donner Land Trust is attempting to treat Donner Lake’s sandy dead zone by acquiring land and restoring it to a natural state. The trust has bought or been given 350 acres of land in the canyon and wants to acquire 110 more acres to protect the canyon and allow public access, Taddo said.

Geomorphologist Cyndie Walck pointed to part of the canyon that had widened to more than 100 feet across. A state park official, Walck said in the past that stretch of stream would have consisted of several narrow channels meandering through a lush meadow.

The combination of logging, four-wheel drive roads and railroad development has caused the widening of the streambed at the base of Emigrant Canyon, in turn destroying its ability to filter sediment.

“The railroad culvert creates a force like a fire hose that blows out the stream bed below,” Walck explained.

In the spring when the snow is melting, water rushes through the culvert with enough force that it can move granite boulders. Wallace recalled the damage of the 1997 floods in Coldstream Canyon that left debris throughout the west end of Truckee and flooded a local gas station.

“We are fairly confident that without the culvert and logging roads [in Coldstream and Emigrant Canyons], there would not been as much damage,” Wallace said.