St Francis Dam Disaster Site

The St Francis Dam

The St Francis Dam was the brainchild of William Mulholland. General Manager and chief engineer for the Los Angeles Department of Water and Power (at the time named Bureau of Water Works and Supply). This concrete gravity Dam was built and designed between 1924-1926. The new Dam was to be a storage reservoir for the rapidly growing city of Los Angeles. Mulholland believed it was important to have this backup water supply should extended drought or damage occur to the Aqueduct. A site was selected 10 miles north of Santa Clarita in San Francisquito Cyn. Mulholland was a smart man and already famous for his design and construction of the 233 mile Los Angeles Aqueduct. An engineering marvel, and at the time the longest of its kind using gravity alone to propel water from the Owens Valley to Los Angeles. (This Aqueduct is still in use today). After extensive testing was done on the San Francisquito Cyn area final construction was carried out by Stanley Dunham and crew. 

The dam after the collapse

This section was named the "Tombstone"

Two and a half minutes before midnight on March 12, 1928 the 185-foot high Dam collapsed sending over 12 billion gallons of water roaring through San Francisquito Cyn and on through the Santa Clara River Valley 54 miles until finally emptying into the Pacific Ocean. Over 450 lives are estimated to have been lost in the flood. The destruction triggered numerous power outages and the shear force of the water destroyed anything in its path. Giving you an idea of the forces at work here A 10,000 ton piece of the dam was carried 3/4 of a mile below the site. First casualty was most likely the dam keeper caught in the 140 high initial wave that crushed his cottage just below the dam. His body and his 6 year old sons body were never found. 1.5 miles downstream Powerhouse #2 was hit and destroyed by a 120 foot wave travelling roughly 18 miles per hour, 64 men and their families who worked and lived nearby were killed as well. Extensive damage was done too Saugus, Valencia, Newhall, Castaic, Filmore, Bardsdale and Santa Paula. South of Ventura debris and victims were emptied into the Pacific. Some bodies were found as far south as the Mexican border and many were never recovered. A horrible tragedy indeed this was.

Concrete Block found half mile below the Dam

From investigative reports at the time I reckon that no matter how well the dam was constructed it most likely was gonna be a ticking time bomb destined to fail. In short Parts of the foundations were placed upon red conglomerate rock, much more easily erodible than solid bedrock. Below are the report conclusions word for word that can be found on Wikipedia. 

1. The type and dimensions of the dam were amply sufficient if based on suitable foundation.
2. The concrete of which the dam was built was of ample strength to resist the stresses to which it would normally be subjected.
3. The failure cannot be laid to movement of the earth's crust.
4. The dam failed as a result of defective foundations.
5. This failure reflects in no way the stability of a well designed gravity dam properly founded on suitable bedrock

Visiting what now remains of the Dam today makes for a great family friendly Hike. There are multiple mileage options to suit everyone's needs. The walk out and back from the upper parking area can be done in under a mile. From the Lower lot one can make it a 3.2 mile round trip or a 1.6 mile shuttle if you have a vehicle parked on each side. (See Map below for way-points and location).

Lower Parking Turnout 

Upper Parking Turnout.

St Francis Dam sits along an old abandoned  section of San Francisquito Rd. The photos above show the parking turnouts and white blockades that keep out vehicle traffic. Not interested in walking, no problem bring your bicycles the old road is still in good enough shape to ride on. 

Follow the debris field across the western section to the hidden register

My daughter standing atop the western Dam section looking toward where the "tombstone" once stood

Before Beginning the hike down or up the old Road I highly recommend walking across the top Western section of the Damn. This affords outstanding views of the surrounding area and down toward what was the curved section of the Dam that blew-out. It's also fun to explore the rubble up here and sign the hidden Dam register while your at it. (Please leave all contents you find in the metal box). To access the western section there are two turnouts off the main San Francisquito Hwy just before the  upper parking turnout. Both have spur trails that will lead you up to the top. The sections are very short but steep. After visiting the western section return to the car and proceed to either the lower or upper Parking area to begin your hike. (Again map below has all relevant way-points).

Hidden Register

Heading down the old road from the upper parking area

Besides visiting the old Dam there are other interesting features along this hike. Make sure to visit the flowing creek and large pool that sits hidden off the trail on the east side of the Dam. As you can see Lot's of disappointing paintings on the rocks next to the plunge pool. Please don't contribute to the vandalism going on here.

The Creek was flowing

secluded pool on eastern side of the Dam,

A short distance below the dam you will cross over an old bridge if you look west you can spot 2 white Memorial crosses near a big boulder section that broke off and was washed downstream. I reckon this was near the area where the Dam keeper once lived.

White memorial crosses placed near large boulder section of the Dam

Haylee with grandpa under the bridge

There are also two nice memorials to see on your drive up the Canyon, one placed at the Fire Station and one at Powerhouse #2. Stop in to see the old photos and read a little bit of the history if you have time.

Memorial at the Fire Station just below the Dam

Memorial at Powerhouse #2

This was definitely a nice little outing with the family, got some exercise and learned a few things. If your a historical nerd like myself I think you would enjoy this one. Lot's to explore and so close to home. Another fine outing in the Angeles National Forest.