When the St. Francis Dam crumbled near midnight on March 12, 1928, residents of the Santa Clara Valley from what is now Santa Clarita in Los Angeles County to Santa Paula in Ventura County were unprepared for the destructive wall of water that poured down the Santa Clara River through the towns of Fillmore, Bardsdale, Santa Paula and Rancho Camulos (now a National Historic Site) in Piru.

The dam was located in the San Francisquito Canyon about 50 miles east of Fillmore and 10 miles north of what is now Santa Clarita (the city wasn’t incorporated until 1987). When it collapsed, it ran for 55 miles through Castaic Junction and down the Santa Clara River before it emptied out into the Pacific Ocean. By the time the flood subsided, it had killed at least 431 people and carved a path of destruction in Ventura County, especially through Fillmore and Santa Paula.

And yet, for many, it remains a mystery. Even noted historian John Nichols, a Santa Paula writer and photographer who runs a gallery at the Santa Paula Art Museum, didn’t find out about it until he moved to Santa Paula.

“I was born in California,” said Nichols. “I grew up in California, I was a history major. I never heard of it until I moved to Santa Paula.”

The dam’s collapse is a story of hubris, greed and a lack of technical and geological knowledge. And yet, even with the lessons learned from that disaster, the Santa Clara Valley remains surrounded by dams; and the same “out of sight, out of mind” thinking is true today.

Martha Gentry, president of the board of directors for the Fillmore Historical Museum, wonders if we in Ventura County live today under the same shadow of vulnerability.

“There’s some of us who think about the Piru Dam, the Pyramid Dam and the dam at Lake Castaic,” Gentry said. “If you have a major earthquake, well, I don’t think people worry any more about those dams then they do a major earthquake. But if those three dams went in an earthquake, that would pretty much wipe out this valley.”

Think Oroville Dam last summer and the panic that set in when the spillways threatened to crumble. Dam failures are rare, but as the residents of the Santa Clara Valley learned 90 years ago, accidents can happen.

The 90th anniversary of the dam’s collapse is being commemorated around the area, and several activities will take place throughout northern Los Angeles County and in eastern Ventura County. Some of these events will involve tours to the old dam site; some will recall the history, and some will even recall acts of heroism. Here is a summary of what you can find during March. For in-depth information about the St. Francis dam events, visit saintfrancisdam.com.

Newhall

March 10, 11 a.m.-4 p.m. Annual St. Francis Dam lecture and bus tour, Saugus Train Station. Special Presenters: Dr. Alan Pollack, Frank Rock, Dianne Erskine-Hellrigel. $40 per person pre-paid ($45 at the door per person), 24101 Newhall Avenue, Newhall, 661-254-1275, www.scvhs.org.

Piru

March 18, 1-7 p.m. St. Francis Dam Disaster Commemoration, Rancho Camulos Museum. Free. 5164 E Telegraph Road, Piru, 521-1501, ranchocamulos.org.

Fillmore

March 17, 9 a.m.-5:30 p.m. 90th Anniversary of St. Francis Dam Commemoration, starting in front of Fillmore City Hall, with a presentation by Jon Wilkman, Dianne Erskine-Hellrigel and Alan Pollack. 250 Central Ave., Fillmore, 524-3701. A train ride to and guided tour of the St. Francis Dam site will also be offered at 12:30 p.m., $40 per person. Contact Martha Gentry, 524-0948, fillmore.museum@sbcglobal.net or fillmorehistoricalmuseum.org.

Santa Paula

March 3-July 8. The California Oil Museum will feature the exhibit When Dams Fail: Lessons Learned From St. Francis and Other Notable Incidents. $4 donation. 1001 E. Main St., Santa Paula, 933-0076, www.caoilmuseum.org.

March 12, noon: A talk on the dam disaster by John Nichols, Peggy Kelly and Carlos Juarez will be given at the Santa Paula Rotary Club meeting at Flight 126 Café at the Santa Paula Airport, 28 Wright Taxi Way, Santa Paula, 933-1155, www.santapaularotary.org.

March 12, 7 p.m.: St. Francis Dam Disaster Candlelight Memorial, Ebell Park, corner of Main and Seventh streets, Santa Paula, scvhistory.com/scvhistory/santapaula031218.htm.

March 15, 5:30-8:30 p.m. Santa Paula Historical Society annual dinner, featuring a presentation by Jon Wilkman. Palazzio Event Center, 814 E. Main St., Santa Paula, $50 per person. Contact Ed Arguelles, 279-3415, epargue@verizon.net or www.santapaulahistoricalsociety.org.