What began as a 150 foot wall of water had subsided to 55 feet of mud, boulders and debris when the flood roared out of San Francisquito canyon toward a sleepy Saugus, then a small town of perhaps a couple hundred souls.

Several small buildings at the substation were destroyed, among them some of the Edison workers' cottages, as "a thick layer of sand, gravel and debris ... pushed south over the Santa Clara River channel" (Hundley & Jackson 2015:144). The substation was inundated and the transformer yard was littered with debris
Southern California Edison's Saugus Substation in the aftermath of the 1928 St. Francis Dam Disaster.
The substation was built between August 1923 and August 1924 on the south/west side of today's Magic Mountain Parkway in what is now Valencia. It replaced the smaller 1899 Castaic Substation. What began as a 150 foot wave had subsided to 55 feet when the flood roared out of San Francisquito canyon toward a sleepy Saugus.
The night crew at the Substation "didn't need a wake-up call," historian John Wilkman writes, when the St. Francis Dam failed just before midnight on March 12. "They were startled into action when an oil switch exploded, setting off a fire. ... Something had gone terribly wrong and no one was sure what caused it" (Wilkman 2016:94).
"Less than forty minutes after the collapse," Wilkman writes, "the leading edge of the flood emerged from the confines of San Francisquito Canyon and widened. ... By now, the oil switch fire was under control. Frank Thees was standing outside with other employees:
We heard a roaring noise which at first we thought was a train on the tracks near the highway. We soon realized ... that a large volume of water was running down the Santa Clara River. ... One of the Big Creek lines flashed over and lit up the entire country, showing us that water was already across the highway (ibid.:97).
Several small buildings at the substation were destroyed, among them some of the Edison workers' cottages, as "a thick layer of sand, gravel and debris ... pushed south over the Santa Clara River channel" (Hundley & Jackson 2015:144). The substation was inundated and the transformer yard was littered with debris — as seen at left in the photograph above.
https://scvhistory.com/
Download the History Cake app to experience this story with automatic audio narration as you visit the location.