Originally constructed in the 1850’s for hydraulic mining, the Main Tuolumne Ditch or Canal includes two miles of elevated wooden flumes and provides the drinking water to over 90% of Tuolumne County.

I’ve made numerous trips to Gold Country over the past three years. This latest trip began in Nevada City to check out the 1969 Frolic vintage trailer I’m purchasing in order to spend even more time at the Wild Burro Rescue volunteering my time, organizing events and working on getting some other programs up and running there in 2019.

After checking out my new trailer, I spent the rest of the day exploring Malakoff Diggins State Historic Park

…before heading to the Airbnb Airstream in Sonora I always use as my home base when I’m out exploring in California’s Gold Country.

The area where I decided to park my Jeep and begin the hike was approximately 15 miles from Sonora, CA.

Using coords (38.062356, -120.210251) I found using Google Maps, I was looking at an approximately 8-mile RT hike. For a longer route, start from the Sierra Pines Golf Course parking area in Twain Harte and head northeast towards Lyons to create a 10-mile RT hike.

The walk from where I parked my Jeep, up to the ditch where I would begin my hike, was a little over 200-feet.

Since I couldn’t see where I parked from the trail, I wedged a piece of bark I found on the ground into a stump to help guide me back to my car when I returned.

Fortunately, I was also able to use this marker along the trail which I found shortly after beginning my hike. The numbers indicate how many miles away you are from Lyons Reservoir.

A network of meandering open ditches…

…and flumes have been used to deliver water throughout Tuolumne County since the gold rush days.

This hike includes over 2 miles of elevated wooden flumes, so if you’re afraid of heights don’t even think about doing it.

Yankee engineers scouted the Sierra for suitable rivers and possible conveyance routes to carry the water through rugged terrain to the gold fields below.

The result was a well-engineered system of flumes, ditches, and canals at two percent grade.

All totaled, over 250 miles of hand-dug ditches distributed water to all corners of the county.  – Source

More than 72 miles of these ditches, canals and flumes still snake through the county today, connecting Lyons Reservoir to water systems that serve communities from Twain Harte to Tuolumne, Bill Hill, Columbia, Sonora, Jamestown and Cedar Ridge.

The ditch systems were originally built in the early 1850s by developers who wanted to get water from the South Fork of the Stanislaus River to lower elevation mining operations. Pacific Gas & Electric later entered the picture when it built Strawberry Reservoir in nearby Pinecrest, CA and began diverting a portion of the river’s flow for power generation.

PG&E owned the entire ditch system until 1893, when the state Public Utilities Commission (PUC) ordered PG&E to pipe the entire network. Instead, PG&E ceded its water conveyance system to Tuolumne County’s water division (Tuolumne Utilities District or TUD), which was not bound to follow the PUC’s orders.

The only painted graffiti I saw along the entire trail.

The landscape along the hike consists of steep hillsides, knolls, and gently sloping meadows. Stands of chaparral are found on the hillsides, interspersed with stands of oak and pine, with grasslands in the meadows and open slopes.

A beach along the trail.

The ditches and their systems were originally constructed to provide water for mining the rich tertiary gravels and the limestone belt, primarily around Columbia, but were soon extended to other placer mining camps and areas, to the hard rock mines during the Second Gold Rush of the late 1880s-1900s, and eventually were altered, expanded, and enlarged to serve agricultural and community needs.

“The majority of the early system was constructed in the 1850s to supply water to the placer mines, especially to the Columbia basin district. With the general exodus from the county after the placers were exhausted, many of the ditches were abandoned, but the hard-rock milling lodes later revived the industry and new laterals were dug to supply the quartz mines.”  – Source

“Gold was discovered in the streams and drainages of the Stanislaus and Tuolumne rivers and their tributaries as early as 1848. Except during the rainy season and spring, the diggings were often dry, with too little water available to wash gold from the gravels. A few springs provided enough water for eating and bathing purposes, and when dammed, a small pond for panning the gold, but by 1850 the horde of miners who had poured into the area began to look for additional sources to provide a year-round supply of water.”  – Source

Plausible sources were the creeks and rivers higher in the foothills, principally the watersheds of the South and Middle forks of the Stanislaus River and the North Fork Tuolumne River and their tributaries.

Most other major drainages had ditches or small dams as well, and were often dammed later in the 19th century for hydropower generation.

By 1853, within five years of the gold “discovery,” most easily retrievable gold had been recovered. Thus, decreasing quantities of placer gold and the need for vast quantities of water to mine in new ways and areas spurred the development of large-scale water storage and conveyance systems.

A colorful old “Property Boundary” sign along the trail.

In a few short years, hundreds of miles of flumes and canals were built in Tuolumne County.

During the 1890s, the Tuolumne County Water Company (TUD) rebuilt the ditches and flumes, built a new dam at Lyons, and constructed the first Phoenix Powerhouse. Although the largest in the county at the time, it was not the first or only. As early as October 1, 1892, the Sonora Electric Light Company had a small hydroelectric plant located on Wood’s Creek at Brown’s Flat, and furnished enough power for 600 homes and businesses to light one light bulb in each.

The TUD today is a water and wastewater utility serving nearly 44,000 residents in Tuolumne County. It provides drinking water for homes, schools, and businesses, as well as recycled water from its wastewater treatment plant to irrigate prime agricultural lands near Jamestown. As the successor to the many smaller water companies that comprise its history, it has changed from a utility serving mainly mining operations to one that serves the residential, commercial, and industrial sectors of Tuolumne County.

“The Tuolumne Utilities District (TUD) receives its water supply from the Sierra Snowpack. This water is delivered to TUD starting at the South Fork of the Stanislaus River at Lyons Reservoir via the Tuolumne Main Canal by agreement with Pacific Gas and Electric Company (PG&E). PG&E still owns and operates Pinecrest Lake, Lyons Reservoir and the Tuolumne Main Canal.”  – Source

“In the summertime, TUD normally receives stored water first from Lyons Reservoir, then second from water stored in Pinecrest Lake. Approximately, 95% of TUD’s customers receive water supplied through the Main Canal into the ditch conveyance system, 5% of water is supplied through wells.”  – Source

These flat rocks were a great place along the trail to enjoy my lunch.

“End of Spill” is a point in time that occurs after the snow has melted and flow in the River has subsided to where the flow out of Lyons Reservoir exceeds the flow into it. The “End of Spill” occurs at the end of the spring snow-melt runoff which typically occurs about July 1st or later.

“At this point in time, water stored in Lyons Reservoir is relied upon to supply Tuolumne County through the summer. However, Lyons Reservoir is relatively small and only holds enough water to support normal Tuolumne County water needs for about 65 days. This span of time normally stretches between about July 1st and Labor Day of each year. After Labor Day, water is normally drawn down from Pinecrest Lake to supplement Lyons Reservoir through the fall and early winter.”  – Source

The upper ditches are heavily wooded, largely with sugar pine, ponderosa pine, incense cedar, and Douglas-fir, requiring extensive clearing of large timber.

An interesting symbol carved into a stump along the trail.

A bend in the ditch.

In 2015, TUD officials described the PG&E Main Canal of flumes and ditches as Tuolumne County’s “Achilles heel” due to the fact that a devastating fire, landslide or earthquake could cut off the drinking water supply to over 44,000 people for over a month or more (up to 500 days).

“There Water?”

Main Canal Spill 1

PG&E has slowly begun to replace the older wooden plank walkways with these sturdier more fire resistant ones.

It looks like these will be the next ones to be replaced.

The views open up as you get closer to Lyons Reservoir.

Stairways allow access to the numerous fire/access roads that parallel the trail.

The Sierra Nevada Conservancy recently allocated $496,000 to construct a fuel break that will increase the Tuolumne Main Canal’s resiliency in the event of a major wildfire.

The last mile of the trail is all flumes.

It starts off fairly close to the ground…

…but slowly begins to rise higher and higher.

Again, if you’re afraid of heights I wouldn’t recommend this adventure, especially since there’s always water flowing in the flumes which can pose even more of an issue for people who experience vertigo.

As I got closer to the dam I started to hear voices and lots of other noise in the distance. It ended up being some PG&E employees working on the flume which cut off my access to Lyons Reservoir. I was totally bummed that I wouldn’t be able to reach the dam but figured I could now use the extra time to explore Yosemite which was the next destination on my list.


Protecting and preserving historic, sacred, and sensitive sites should be practiced by all. Locations, directions, and names to some of the places found on this site are not listed, please don’t ask for them. Tread lightly, leave no trace and always respect the wonder that surrounds you.