St. Francis Dam - Collapse and Flood Wave

Collapse and Flood Wave

Two and a half minutes before midnight on March 12, 1928, the St. Francis Dam catastrophically failed.

Although there were no eyewitnesses to the dam's collapse itself, it is known that no less than four separate people passed the dam within an hour of the failure and none of them noticed any conditions which were out of the ordinary. A motorcyclist named Ace Hopewell had ridden past the dam, by his approximation, ten minutes before midnight. In his testimony at the Coroner's Inquest, he stated that he rode up the canyon and had passed both Powerhouse No. 2 (a hydroelectric power plant) and the dam without seeing anything which would cause concern. Although, he went on to state that at approximately one mile (1.6 km) upstream of the dam he heard, above the sound of his motorcycle, what to him was much like "rocks rolling down the mountain." He stopped and checked the hillsides above him. The sound which he had heard earlier was behind him, and he assumed this had possibly been a landslide, as these were common to the area. It is believed that he was the last person to have seen the St. Francis Dam intact.

As the dam collapsed, the reservoirs 12.4 billion U.S. gallons (45 billion liters or 45 million m³) of water began to surge down San Francisquito Canyon in a dam break wave. The dam keeper and his family were most likely the first casualties caught in the flood wave, which was at about 140 ft (43 m) high when it hit their cottage, approximately 1/4 mile (400 m) downstream from the dam. The body of Leona Johnson, the woman who lived with the Harnischfegers (often mistakenly reported later as Harnischfeger's wife) was found fully clothed and wedged between two blocks of concrete near the base of the dam. This led to the suggestion she and the dam keeper may have been inspecting the dam immediately prior to its failure. Neither Tony Harnischfeger's body nor that of his six-year-old son, Coder, were ever found.

Five minutes after the collapse, having traveled a distance of one and one-half miles (2.4 km) at an average speed of 18 miles per hour, the now 120-foot-high (37 m) flood wave demolished the heavy concrete Powerhouse No. 2 and took the lives of 65 of the other 67 workmen and their families who lived nearby. The water traveled south down the canyon and emptied into the Santa Clara riverbed flooding parts of present-day Valencia and Newhall. The deluge, now 55 feet high,, then followed the river bed west, washing away the town of Castaic Junction. Continuing on into Ventura County.
The Santa Clara Valley's lone telephone operator, Louise Gipe, was at her station located in Santa Paula when she received a message shortly before 1:30 a.m. that the St. Francis dam had broken and a tremendous wall of water was sweeping down the valley. She was given orders to notify the authorities and then warn those who lived in the low lying areas. She immediately called Highway Patrolman Thorton Edwards, who lived in Santa Paula, and then began calling the homes of those in danger. Edwards, within a short time joined by another officer, Stanley Baker, used their motorcycles to awaken and warn residents by leaving their sirens running and criss-crossing the streets in the danger zone. The two policemen continued this until the rising floodwater forced their retreat. The flood devastated much of the towns of Fillmore, Santa Paula and Bardsdale before emptying its victims and debris into the Pacific Ocean near Ventura at Montalvo at 5:30 a.m. The flood had taken only 5 hours and 27 minutes to travel the 54 miles (87 km) from the reservoir and dam site. At this time, it was almost two miles (3 km) wide and traveling at a speed of 6 miles (8 km) per hour. Bodies of victims were recovered from the Pacific Ocean, some as far south as the Mexican border.

Newspapers across the country carried accounts of the disaster. The front page of the Los Angeles Times ran four stories, including aerial photos of the obliterated dam, the city of Santa Paula after its wake and a partial list of the dead. It also set up a Times Flood Relief Fund, to receive donations from around the country. The Times also reported that Mullholland issued a statement saying, "I would not venture at this time to express a positive opinion as to the cause of the St. Francis Dam disaster." "Mr. Van Norman and I arrived at the scene of the break around 2:30am this morning. We saw at once that the dam was completely out and that the torrential flood of water from the reservoir had left an appalling record of death and destruction in the valley below." In the article, Mullholland stated that it appeared that there had been major movement in the hills forming the western buttress of the dam. He added that three eminent geologists, Robert T. Hill, C. F. Tolman and D. W. Murphy had been hired by the Board of Water and Power Commissioners to determine if this was the cause. It was noted that there were no tremors reported at seismograph stations and an earthquake could be ruled out as the cause of the break.