January 16, 2014

Photo Essay: The Power Plants of the St. Francis Dam Disaster

[Last updated 4/7/19 7:31 PM PT—photo added]

I've been fascinated with the story of the St. Francis Dam Disaster for a while, partially because of my interest in both disaster sites and ruins, but also because of its place in LA's water history.

After all, you can't really understand the Dam without understanding the significance of the opening of the Los Angeles Aqueduct, and how that water supply (and resulting electrical power) helped make LA the thriving metropolis it is today.

Fifteen years before the St. Francis Dam broke in 1928, killing over 450 with a surging wall of water 180 feet high, the LA Aqueduct opened, and it became the crowning glory of the career of LA's chief engineer of water and power, William Mulholland (of Mulholland Drive fame).

Water pipe north of Power Plant #1, circa 2019

Once LA figured out how to actually get water from somewhere else (the Owens Valley), we had to figure out what to do with it: how to control its flow, how to convert it into usable power, and how to store a surplus, emergency supply.

Power Plant #1 was built and put into operation in 1917, primarily to control the flow of the water from the Owens Valley.

image courtesy of Water and Power Associates

Although the Aqueduct itself extends over 200 miles north of Power Plant #1 to its intake in Bishop, the pipes leading down to this plant mark the first real arrival of water to LA - over 20 miles north of the Cascades. If you venture into San Francisquito Canyon, down a road marked "PRIVATE" into a small company town called Pelton (built along the old Butterfield Stagecoach Road for the plant workers who have to be on call all day and all night, every day)... find a number of relics of LA's former Bureau of Water and Power, including a rusty old DC current generator...

...dollies, a debris car, a section of the first Los Angeles Aqueduct "tube," a reaction turbine...

...and a wooden cable reel, only a few of which remain in use, as they've been cycled out in favor of metal reels for cable-pulling operations.

Power Plant #1's sprawling property in Pelton has become somewhat of a repository for decommissioned equipment and relics found deep under brush, from as far as Owens Valley to as nearby as the San Fernando Valley Generating Station in Sun Valley (like this tool trailer), Elizabeth Lake, and Power Plant #2, also in San Francisquito Canyon.

Although Power Plant #1 is currently in operation - much in the same way it was when it first opened - a visit to it feels like a step back in time. The name of the agency may have changed - the Bureau of Water and Power is now the LADWP - but the building has not.

Water still flows down the penstocks (intake tubes) built into the cliff behind the plant...

...bringing water to it, and the sound of waves.

Inside the power plant...'s loud. Really loud.

There's a lot of big, old equipment like Pelton wheels and Westinghouse alternating current generators...

...which are mostly original to the construction of the building, occasionally needing a repair or upgrade (mostly for efficiency purposes). When working properly, they run all of the time.

There are also gauges that measure the pressure of the water flowing through...

...and the three-cylinder, belt-driven pump that's not on all of the time, but sure made a racket when he turned it on.

For the most part, while standing in this facility, you experience working history that most people never visit, or even know about, but modern equipment has, in some cases, been added.

It hasn't necessarily improved the workings of the plant.

In many ways, the processes of this power plant have been mechanized and automated enough to be relatively self-sufficient. The technology of the Westinghouse temperature indicating device used here dates back to 1920, though it does require occasional manual spot checks on water temperature (which should be "warmish").

But this power plant is instrumental in the success of the functionality of the entire region, with a control room overlooking the generators below. From there, they can monitor and report on a total of six power stations in the area.

Workers know when a door is ajar.

Water levels, temperatures, pressure, and equipment functionality are all monitored for local reservoirs and pipelines.

Voltage is measured in megawatts, hertz, kilovolts, and megavars.

If disaster were to strike again at any of those local facilities... it did in 1928 when the St. Francis Dam broke...

...Power Plant #1 would be ground zero.

(In fact, one of the first indications that something was wrong at the St. Francis Dam was the flickering of lights and odd power surges in the middle of the night.)

Located upstream from the dam site, Power Plant #1 was thankfully spared from the raging flood waters and suffered no damage from the break, but Power Plant #2 - located about a mile and a half downstream from the dam - was wiped away.

The water spilling through the dam from the reservoir took everything in its wake: trees, livestock, people, and buildings.

Miraculously, the inner workings of Power Plant #2 - generators bolted to a concrete floor - were spared and completely functional once the water receded.

Two of those turbines are still in use today, inside the rebuilt Power Plant, which was back up and running in November 1928, eight months after the dam broke.

The rebuilt Power Plant #2 was far more architecturally ornate than its 1920 predecessor, or its 1917 sister plant up the canyon, with colorful Art Deco stylings.

Power Plant #2 is visible from San Francisquito Canyon Road just south of the dam site, and is worth a visit to see the penstocks behind the building (two original, one replaced), and a historical marker for the dam disaster, located behind a chainlink fence by the front driveway. The public is not allowed inside the plant.

Stay tuned for more explorations of Old San Francisquito Canyon Road, and the remains of the St. Francis Dam at the disaster site.

Related Posts:
Celebrating the LA Aqueduct Centennial at The Cascades
Photo Essay: Burbank Water and Power Eco-Campus


  1. My father workes at power plant #1 in 40s. So did our neighbor, who told of himsself and wife clinging to their mattress as they were swept way way down the canyon.

  2. One morning the mountain behind power plant #2 was full of lights. Me and a buddy saw it on the way to work around 5am. Can anyone confirm if the mountain behind power plant #2 has lights?