St. Francis Dam

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St. Francis Dam_table_infobox_0

St. Francis DamSt. Francis Dam_header_cell_0_0_0
LocationSt. Francis Dam_header_cell_0_1_0 Los Angeles County, California, United StatesSt. Francis Dam_cell_0_1_1
CoordinatesSt. Francis Dam_header_cell_0_2_0 St. Francis Dam_cell_0_2_1
Construction beganSt. Francis Dam_header_cell_0_3_0 1924St. Francis Dam_cell_0_3_1
Opening dateSt. Francis Dam_header_cell_0_4_0 1926St. Francis Dam_cell_0_4_1
Demolition dateSt. Francis Dam_header_cell_0_5_0 1929St. Francis Dam_cell_0_5_1
Dam and spillwaysSt. Francis Dam_header_cell_0_6_0
ImpoundsSt. Francis Dam_header_cell_0_7_0 Los Angeles Aqueduct

San Francisquito CreekSt. Francis Dam_cell_0_7_1

HeightSt. Francis Dam_header_cell_0_8_0 185 feet (56 m)St. Francis Dam_cell_0_8_1
Height (foundation)St. Francis Dam_header_cell_0_9_0 205 feet (62 m)St. Francis Dam_cell_0_9_1
LengthSt. Francis Dam_header_cell_0_10_0 main dam 700 feet (210 m)

wing dike 588 feet (179 m)St. Francis Dam_cell_0_10_1

Elevation at crestSt. Francis Dam_header_cell_0_11_0 parapet 1,838 feet (560 m)

spillway 1,835 feet (559 m)St. Francis Dam_cell_0_11_1

Width (crest)St. Francis Dam_header_cell_0_12_0 16 feet (4.9 m)St. Francis Dam_cell_0_12_1
Width (base)St. Francis Dam_header_cell_0_13_0 170 feet (52 m)St. Francis Dam_cell_0_13_1
Parapet widthSt. Francis Dam_header_cell_0_14_0 16 ft (4.9 m)St. Francis Dam_cell_0_14_1
Hydraulic headSt. Francis Dam_header_cell_0_15_0 182 ft (55 m)St. Francis Dam_cell_0_15_1
Dam volumeSt. Francis Dam_header_cell_0_16_0 main dam 130,446 cu yd (99,733 m)

wing dike 3,826 cu yd (2,925 m)St. Francis Dam_cell_0_16_1

Spillway typeSt. Francis Dam_header_cell_0_17_0 uncontrolled overflowSt. Francis Dam_cell_0_17_1
ReservoirSt. Francis Dam_header_cell_0_18_0
Total capacitySt. Francis Dam_header_cell_0_19_0 38,168 acre⋅ft (47.080×10^ m)St. Francis Dam_cell_0_19_1
Catchment areaSt. Francis Dam_header_cell_0_20_0 37.5 sq mi (97 km)St. Francis Dam_cell_0_20_1
Maximum lengthSt. Francis Dam_header_cell_0_21_0 3 mi (4.8 km)St. Francis Dam_cell_0_21_1
Maximum water depthSt. Francis Dam_header_cell_0_22_0 182 ft (55 m)St. Francis Dam_cell_0_22_1
California Historical LandmarkSt. Francis Dam_header_cell_0_23_0
Official nameSt. Francis Dam_header_cell_0_24_0 St. Francis Dam Disaster SiteSt. Francis Dam_cell_0_24_1
Reference no.St. Francis Dam_header_cell_0_25_0 919St. Francis Dam_cell_0_25_1

The St. Francis Dam was a curved concrete gravity dam, built to create a large regulating and storage reservoir for the city of Los Angeles, California. St. Francis Dam_sentence_0

The reservoir was an integral part of the city's Los Angeles Aqueduct water supply infrastructure. St. Francis Dam_sentence_1

It was located in San Francisquito Canyon of the Sierra Pelona Mountains, about 40 miles (64 km) northwest of downtown Los Angeles, and approximately 10 miles (16 km) north of the present day city of Santa Clarita. St. Francis Dam_sentence_2

The dam was designed and built between 1924 and 1926 by the Los Angeles Department of Water and Power, then named the Bureau of Water Works and Supply. St. Francis Dam_sentence_3

The department was under the direction of its general manager and chief engineer, William Mulholland. St. Francis Dam_sentence_4

At 11:57 p.m. on March 12, 1928, the dam catastrophically failed, and the resulting flood killed at least 431 people. St. Francis Dam_sentence_5

The collapse of the St. Francis Dam is considered to be one of the worst American civil engineering disasters of the 20th century and remains the second-greatest loss of life in California's history, after the 1906 San Francisco earthquake and fire. St. Francis Dam_sentence_6

The disaster marked the end of Mulholland's career. St. Francis Dam_sentence_7

Planning and design St. Francis Dam_section_0

In the early years of Los Angeles, the city's water supply was obtained from the Los Angeles River. St. Francis Dam_sentence_8

This was accomplished by diverting water from the river through a series of ditches called zanjas. St. Francis Dam_sentence_9

At that time, a private water company, the Los Angeles City Water Company, leased the city's waterworks and provided water to the city. St. Francis Dam_sentence_10

Hired in 1878 as a zanjero (ditch tender), William Mulholland proved to be a brilliant employee, who, after doing his day's work, would study textbooks on mathematics, hydraulics and geology and taught himself engineering and geology. St. Francis Dam_sentence_11

Mulholland quickly moved up the ranks of the Water Company and was promoted to Superintendent in 1886. St. Francis Dam_sentence_12

In 1902, the City of Los Angeles ended its lease with the private water company and took control over the city's water supply. St. Francis Dam_sentence_13

The city council established the Water Department with Mulholland as its Superintendent and when the city charter was amended in 1911, the Water Department was renamed the Bureau of Water Works and Supply. St. Francis Dam_sentence_14

Mulholland continued as Superintendent and was named as its Chief Engineer. St. Francis Dam_sentence_15

Mulholland achieved great recognition among members of the engineering community when he supervised the design and construction of the Los Angeles Aqueduct, which at the time was the longest aqueduct in the world and uses gravity alone to bring the water 233 miles (375 km) from the Owens Valley to Los Angeles. St. Francis Dam_sentence_16

The project was completed in 1913, on time and under budget, despite several setbacks. St. Francis Dam_sentence_17

Excluding incidents of sabotage by Owens Valley residents in the early years, the aqueduct has continued to operate well throughout its history and remains in operation today. St. Francis Dam_sentence_18

It was during the process of building the Los Angeles Aqueduct that Mulholland first considered sections of San Francisquito Canyon as a potential dam site. St. Francis Dam_sentence_19

He felt that there should be a reservoir of sufficient size to provide water for Los Angeles for an extended period in the event of a drought or if the aqueduct were damaged by an earthquake. St. Francis Dam_sentence_20

In particular he favored the area between where the hydroelectric power plants Powerhouses No. St. Francis Dam_sentence_21

1 and No. St. Francis Dam_sentence_22

2 were to be built, with what he perceived as favorable topography, a natural narrowing of the canyon downstream of a wide, upstream platform which would allow the creation of a large reservoir area with a minimum possible dam. St. Francis Dam_sentence_23

A large camp had been set up to house the workers near this area and Mulholland used his spare time becoming familiar with the area's geological features. St. Francis Dam_sentence_24

In the area where the dam would later be situated, he found the mid and upper portion of the western hillside consisted mainly of a reddish colored conglomerate and sandstone formation that had small strings of gypsum interspersed within it. St. Francis Dam_sentence_25

Below the red conglomerate, down the remaining portion of the western hillside, crossing the canyon floor and up the eastern wall, a drastically different rock composition prevailed. St. Francis Dam_sentence_26

These areas were made up of mica schist that was severely laminated, cross-faulted in many areas and interspersed with talc. St. Francis Dam_sentence_27

Although later many geologists disagreed on the exact location of the area of contact between the two formations, a majority opinion placed it at the inactive San Francisquito Fault line. St. Francis Dam_sentence_28

Mulholland ordered exploratory tunnels and shafts excavated into the red conglomerate hillside to determine its characteristics. St. Francis Dam_sentence_29

He also had water percolation tests performed. St. Francis Dam_sentence_30

The results convinced him that the hill would make a satisfactory abutment for a dam should the need ever arise. St. Francis Dam_sentence_31

A surprising aspect of the early geologic exploration came later when the need for a dam arose. St. Francis Dam_sentence_32

Although Mulholland wrote of the perilous nature of the face of schist on the eastern side of the canyon in his annual report to the Board of Public Works in 1911, it was either misjudged or ignored by the construction supervisor of the St. Francis Dam, Stanley Dunham. St. Francis Dam_sentence_33

Dunham testified, at the Coroner's Inquest, that tests which he had ordered yielded results which showed the rock to be hard and of the same nature throughout the entire area which became the eastern abutment. St. Francis Dam_sentence_34

His opinion was that this area was more than suitable for construction of the dam. St. Francis Dam_sentence_35

The population of Los Angeles was increasing rapidly. St. Francis Dam_sentence_36

In 1900 the population was slightly over 100,000. St. Francis Dam_sentence_37

By 1910, it had become more than three times that number at 320,000, and by 1920 the figure reached 576,673. St. Francis Dam_sentence_38

This unexpectedly rapid growth brought a demand for a larger water supply. St. Francis Dam_sentence_39

Between 1920 and 1926, seven smaller reservoirs were built and modifications were made to raise the height of its largest of the time, the Lower San Fernando, by seven feet, but the need for a still larger reservoir was clear. St. Francis Dam_sentence_40

Originally, the planned site of this new large reservoir was to be in Big Tujunga Canyon, above the city now known as Sunland, in the northeast portion of the San Fernando Valley, but the high value placed on the ranches and private land which would be needed were, in Mulholland's view, an attempted hold-up of the city. St. Francis Dam_sentence_41

He ceased the attempts at purchasing those lands and, either forgetful of or disregarding his earlier acknowledgement of geological problems at the site, renewed his interest in the area he had explored twelve years earlier, the federally owned and far less expensive private land in San Francisquito Canyon. St. Francis Dam_sentence_42

Construction and modification St. Francis Dam_section_1

The process of surveying the area and determining the location for the St. Francis Dam began in December 1922. St. Francis Dam_sentence_43

Clearing of the site and construction began without any of the usual fanfare for a municipal project of this nature. St. Francis Dam_sentence_44

The Los Angeles Aqueduct had become the target of frequent sabotage by angry farmers and landowners in the Owens Valley and the city was eager to avoid any repeat of these expensive and time-consuming repairs. St. Francis Dam_sentence_45

The St. Francis, sometimes referred to as the San Francisquito, was only the second concrete dam to be designed and built by the Bureau of Water Works and Supply. St. Francis Dam_sentence_46

The first was the nearly dimensionally identical Mulholland Dam, on which construction had begun one year earlier. St. Francis Dam_sentence_47

The design of the St. Francis was in fact an adaptation of the Mulholland Dam with certain changes which were made so as to suit the location. St. Francis Dam_sentence_48

Most of the design profiles and computation figures of stress factors for the St. Francis came from this adaptation of the plans and formulas which had been used in the constructing of Mulholland Dam. St. Francis Dam_sentence_49

This work was done by the Engineering department within the Bureau of Water Works and Supply. St. Francis Dam_sentence_50

In describing the shape and type of the St. Francis Dam the word curved is used although, by today's standards, due to the amount of curve in its radius, the dam would be considered arched and therefore making it of the gravity-arch design. St. Francis Dam_sentence_51

It is not so called because the science of gravity-arch dams was still in its infancy and little was known in the engineering community about the arch effect, how it worked and how loads were transmitted, other than that it did help with stability and support. St. Francis Dam_sentence_52

As such, the dam was designed without any of the additional benefits given by the arch action, which led to its profile being considered conservative given its size. St. Francis Dam_sentence_53

Annually, as did most other city entities, the Bureau of Water Works and Supply and the ancillary departments reported to the Board of Public Service Commissioners on the prior fiscal year's activities. St. Francis Dam_sentence_54

From these we know that the preliminary studies of the area which became the site of the dam, and topographical surveys for the St. Francis reservoir and dam, were completed by June 1923. St. Francis Dam_sentence_55

They called for a dam built to the elevation of 1,825 ft (556 m) above sea level, which is 175 ft (53 m) above the stream bed base. St. Francis Dam_sentence_56

These early calculations for a reservoir created by the dam revealed it would have a capacity of approximately 30,000 acre⋅ft (37,000,000 m) St. Francis Dam_sentence_57

On July 1, 1924, the same day Mulholland was to submit his annual report to the Board of Public Service Commissioners, Office Engineer W. W. Hurlbut informed him that all of the preliminary work on the dam had been completed. St. Francis Dam_sentence_58

In his report presented to the Board, Mulholland wrote that the capacity of the reservoir would be 32,000 acre-feet (39,000,000 m). St. Francis Dam_sentence_59

Hurlbut, who also presented the Board with his annual report, Report of the Office Engineer gave a clarification for this change from the prior year's estimate. St. Francis Dam_sentence_60

In his report he wrote that St. Francis Dam_sentence_61

Construction of the dam itself began five weeks later, in early August, when the first concrete was poured. St. Francis Dam_sentence_62

In March 1925, prior to Mulholland's report to the Board of Public Service Commissioners, Office Engineer Hurlbut again reported to Mulholland on the progress of the St. Francis Dam and reservoir. St. Francis Dam_sentence_63

He stated the reservoir would now have a capacity of 38,000 acre-feet (47,000,000 m) and that the dam's height would be 185 feet (56 m) above stream bed level. St. Francis Dam_sentence_64

Hurlbut wrote, in an explanation of these changes that was presented to the Board of Public Service Commissioners, that St. Francis Dam_sentence_65

This 10-foot (3.0 m) increase in the dam's height over the original plan of 1923 necessitated the construction of a 588-foot (179 m) long wing dike along the top of the ridge adjacent to the western abutment in order to contain the enlarged reservoir. St. Francis Dam_sentence_66

A distinctive aspect of the St. Francis Dam was its stepped downstream face. St. Francis Dam_sentence_67

While the height of each step was a constant 5 feet (1.5 m), the width of each step was unique to its respective elevation above sea level. St. Francis Dam_sentence_68

This width varied between 5.5 feet (1.7 m) near the stream bed base at 1,650 feet (500 m) and decreased to 1.45 feet (0.44 m) at an elevation of 1,816 feet (554 m), the base of the spillways and upright panels. St. Francis Dam_sentence_69

When completed on May 4, 1926, the stairstep faced dam rose to a height of 185 feet above the canyon floor. St. Francis Dam_sentence_70

Both faces leading up to the crest were vertical for the final 23 feet (7.0 m). St. Francis Dam_sentence_71

On the downstream face, this vertical section was fashioned into 24 feet (7.3 m) wide sections. St. Francis Dam_sentence_72

A portion of these made up the spillway, which consisted of 11 panels in total divided into two groups. St. Francis Dam_sentence_73

Each spillway section had an open area that was 18 inches (46 cm) high and 20 feet (6.1 m) wide for the overflow to pass. St. Francis Dam_sentence_74

The dam also had five 30-inch (76 cm) diameter outlet pipes through the center section which were controlled by slide gates attached to the upstream face. St. Francis Dam_sentence_75

Dam instability St. Francis Dam_section_2

Water began to fill the reservoir on March 12, 1926. St. Francis Dam_sentence_76

It rose steadily and rather uneventfully, although several temperature and contraction cracks did appear in the dam and a minor amount of seepage began to flow from under the abutments. St. Francis Dam_sentence_77

In accord with the protocol for design, which had been established by the engineering department during construction of the Mulholland dam, no contraction joints were incorporated. St. Francis Dam_sentence_78

The most notable incidents were two vertical cracks that ran down through the dam from the top. St. Francis Dam_sentence_79

One was approximately fifty-eight feet west of the outlet gates and another about the same distance to the east. St. Francis Dam_sentence_80

Mulholland, along with his Assistant Chief Engineer and General Manager Harvey Van Norman, inspected the cracks and leaks and judged them to be within expectation for a concrete dam the size of the St. Francis. St. Francis Dam_sentence_81

At the beginning of April, the water level reached the area of the inactive San Francisquito Fault line in the western abutment. St. Francis Dam_sentence_82

Some seepage began almost immediately as the water covered this area. St. Francis Dam_sentence_83

Workers were ordered to seal off the leak, but they were not entirely successful and water continued to permeate through the face of the dam. St. Francis Dam_sentence_84

A two-inch pipe was used to collect this seepage and was laid from the fault line down to the home of the dam keeper, Tony Harnischfeger, which he used for domestic purposes. St. Francis Dam_sentence_85

Water that collected in the drainage pipes under the dam to relieve the hydrostatic uplift pressure was carried off in this manner as well. St. Francis Dam_sentence_86

In April 1927 the reservoir level was brought to within ten feet of the spillway, and during most of May the water level was within three feet of overflowing. St. Francis Dam_sentence_87

There were no large changes in the amount of the seepage that was collected and, month after month, the pipe flowed about one-third full. St. Francis Dam_sentence_88

This was an insignificant amount for a dam the size of the St. Francis, and on this subject Mulholland said, "Of all the dams I have built and of all the dams I have ever seen, it was the driest dam of its size I ever saw." St. Francis Dam_sentence_89

The seepage data recorded during the 1926–1927 period shows that the dam was an exceptionally dry structure. St. Francis Dam_sentence_90

On May 27 the problems in the Owens Valley escalated once again with the dynamiting of a large section of the Los Angeles Aqueduct, part of the California Water Wars. St. Francis Dam_sentence_91

A second incident took place a few days later which destroyed another large section. St. Francis Dam_sentence_92

In the days that followed, several more sections of the aqueduct were dynamited which caused a complete interruption of the flow. St. Francis Dam_sentence_93

The near-full reservoir behind the St. Francis Dam was the only source of water from the north and withdrawals began immediately. St. Francis Dam_sentence_94

During this time, the Los Angeles Sheriff's Department received an anonymous phone call that a carload of men were on their way from Inyo County with the intention of dynamiting the St. Francis Dam and "to get some officers on the way as quick as possible." St. Francis Dam_sentence_95

Within minutes, all personnel of the Bureaus of Power and Light and Water Works and Supply either working or residing within the canyon had been notified. St. Francis Dam_sentence_96

Cars carrying dozens of officers from both the Los Angeles Police and Sheriff's Department rushed to the area. St. Francis Dam_sentence_97

Although no sign of the threat that brought all this about materialized, for many days after the canyon resembled an armed camp. St. Francis Dam_sentence_98

The Daily Record of High Water Elevations of the St. Francis Dam shows that between May 27 and June 30 alone, 7000 to 8000 acre-feet of water was withdrawn. St. Francis Dam_sentence_99

Through June and July the Owens Valley fight continued, as did interruptions in the flow from the aqueduct. St. Francis Dam_sentence_100

This in turn caused continued withdrawals from the reservoir. St. Francis Dam_sentence_101

In early August, opposition to Los Angeles' water projects collapsed after the indictment of its leaders for embezzlement. St. Francis Dam_sentence_102

The city subsequently sponsored a series of repair and maintenance programs for aqueduct facilities that stimulated local employment. St. Francis Dam_sentence_103

Once again, the St. Francis reservoir level rose, although not without incident. St. Francis Dam_sentence_104

Late in the year a fracture was noticed which began at the western abutment and ran diagonally upwards and toward the center section for a distance. St. Francis Dam_sentence_105

As with others, Mulholland inspected it, judged it to be another contraction crack and ordered it filled with oakum and grouted to seal off any seepage. St. Francis Dam_sentence_106

At the same time another fracture appeared in a corresponding position on the eastern portion of the dam, starting at the crest near the last spillway section and running downward at an angle for sixty-five feet before ending at the hillside. St. Francis Dam_sentence_107

It too was sealed in the same manner. St. Francis Dam_sentence_108

Both of these fractures were noted to be wider at their junction with the hillside abutments and narrowed as they angled toward the top of the dam. St. Francis Dam_sentence_109

The reservoir continued to rise steadily until early February 1928, when the water level was brought to within one foot of the spillway. St. Francis Dam_sentence_110

During this time though, several new cracks appeared in the wing dike and new areas of seepage began from under both abutments. St. Francis Dam_sentence_111

Near the end of February, a notable leak began at the base of the wing dike approximately 150 feet (46 m) west of the main dam. St. Francis Dam_sentence_112

It was discharging about 0.60 cubic feet per second (4.5 U.S. gallons, or 17 liters, per second) and was inspected by Mulholland who judged it to be another contraction or temperature crack and left it open to drain. St. Francis Dam_sentence_113

During the first week of March, it was noticed that the leak had approximately doubled. St. Francis Dam_sentence_114

Due in part to some erosion taking place, Mulholland ordered an eight-inch (20.3 cm) concrete drain pipe to be installed. St. Francis Dam_sentence_115

The pipe led the water along the dike wall, discharging it at the west abutment contact with the main dam. St. Francis Dam_sentence_116

This gave the hillside a very saturated appearance, and the water flowing down the steps of the dam where it abutted the hill caused alarm among the canyon residents and others traveling on the road 700 feet (210 m) to the east, as at that distance it appeared the water was coming from the abutment. St. Francis Dam_sentence_117

On March 7, 1928, the reservoir was three inches below the spillway crest and Mulholland ordered that no more water be turned into the St. Francis. St. Francis Dam_sentence_118

On the morning of March 12, while conducting his usual inspection of the dam, the dam keeper discovered a new leak in the west abutment. St. Francis Dam_sentence_119

Concerned not only because other leaks had appeared in this same area in the past but more so that the muddy color of the runoff he observed could indicate the water was eroding the foundation of the dam, he immediately alerted Mulholland. St. Francis Dam_sentence_120

After arriving, both Mulholland and Van Norman began inspecting the area of the leak. St. Francis Dam_sentence_121

Van Norman found the source and by following the runoff, determined that the muddy appearance of the water was not from the leak itself but came from where the water contacted loose soil from a newly cut access road. St. Francis Dam_sentence_122

The leak was discharging 2 to 3 cubic feet (15 to 22 U.S. gallons, or 57 to 85 liters) per second of water by their approximation. St. Francis Dam_sentence_123

Certainly their concern was heightened not only given its location but more so in that at times the volume being discharged was inconsistent, they later testified at the Coroner's Inquest. St. Francis Dam_sentence_124

Twice as they watched, an acceleration or surging of the flow was noticed by both men. St. Francis Dam_sentence_125

Mulholland felt that some corrective measures were needed although this could be done at some time in the future. St. Francis Dam_sentence_126

For the next two hours Mulholland, Van Norman and Harnischfeger inspected the dam and various leaks and seepages, finding nothing out of the ordinary or of concern for a large dam. St. Francis Dam_sentence_127

With both Mulholland and Van Norman convinced that the new leak was not dangerous and that the dam was safe, they returned to Los Angeles. St. Francis Dam_sentence_128

Collapse and flood wave St. Francis Dam_section_3

Two and a half minutes before midnight on March 12, 1928, the St. Francis Dam catastrophically failed. St. Francis Dam_sentence_129

There were no surviving eyewitnesses to the collapse, but at least five people passed the dam less than an hour before without noticing anything unusual. St. Francis Dam_sentence_130

The last, Ace Hopewell, a carpenter at Powerhouse No. St. Francis Dam_sentence_131

1, rode his motorcycle past the dam about ten minutes before midnight. St. Francis Dam_sentence_132

He testified at the Coroner's Inquest that he had passed Powerhouse No. St. Francis Dam_sentence_133

2 without seeing anything there or at the dam that caused him concern. St. Francis Dam_sentence_134

He stated that at approximately one and one-half miles (2.4 km) upstream he heard above his motorcycle's engine noise a rumbling much like the sound of "rocks rolling on the hill." St. Francis Dam_sentence_135

He stopped and got off, leaving the engine idling, and smoked a cigarette while checking the hillside above him. St. Francis Dam_sentence_136

The rumble that had caught his attention earlier had begun to fade behind him. St. Francis Dam_sentence_137

Assuming that it might have been a landslide, as these were common in the area, and satisfied that he was in no danger, he continued on. St. Francis Dam_sentence_138

At the Bureau of Power and Light at both Receiving Stations in Los Angeles and the Water Works and Supply at Powerhouse No. St. Francis Dam_sentence_139

1 there was a sharp voltage drop at 11:57:30 p.m. St. Francis Dam_sentence_140

Simultaneously, a transformer at Southern California Edison's Saugus substation exploded, a situation investigators later determined was caused by wires up the western hillside of San Francisquito canyon about ninety feet above the dam's east abutment shorting. St. Francis Dam_sentence_141

Given the known height of the flood wave, and that within seventy minutes or less after the collapse the reservoir was virtually empty, the failure must have been sudden and complete. St. Francis Dam_sentence_142

Seconds after it began, little of what had been the dam remained standing, other than the center section and wing wall. St. Francis Dam_sentence_143

The main dam, from west of the center section to the wing wall abutment atop the hillside, broke into several large pieces, and numerous smaller pieces. St. Francis Dam_sentence_144

All of these were washed downstream as 12.4 billion gallons (47 million m³) of water began surging down San Francisquito Canyon. St. Francis Dam_sentence_145

The largest piece, weighing approximately 10,000 tons (9,000 metric tons) was found about three-quarters of a mile (1.2 km) below the dam site. St. Francis Dam_sentence_146

Somewhat similarly, the dam portion east of the center section had also broken into several larger and smaller pieces. St. Francis Dam_sentence_147

Unlike the western side, most of these ended lying near the base of the standing section. St. Francis Dam_sentence_148

The largest fragments fell across the lower portion of the standing section, coming to rest partially on its upstream face. St. Francis Dam_sentence_149

Initially, the two remaining sections of the dam remained upright. St. Francis Dam_sentence_150

As the reservoir lowered, water undercut the already undermined eastern portion, which twisted and fell backwards toward the eastern hillside, breaking into three sections. St. Francis Dam_sentence_151

The dam keeper and his family were most likely among the first casualties caught in the initially 140 feet (43 m) high flood wave, which swept over their cottage about a quarter of a mile (400 m) downstream from the dam. St. Francis Dam_sentence_152

The body of a woman who lived with the family was found fully clothed and wedged between two blocks of concrete near the base of the dam. St. Francis Dam_sentence_153

This led to the suggestion she and the dam keeper may have been inspecting the structure immediately before its failure. St. Francis Dam_sentence_154

Neither his nor his six-year-old son's bodies were found. St. Francis Dam_sentence_155

Five minutes after the collapse, the then 120-foot-high (37 m) flood wave had traveled one and one-half miles (2.4 km) at an average speed of 18 miles per hour (29 km/h), destroying the heavy concrete Powerhouse No. St. Francis Dam_sentence_156

2 there and taking the lives of 64 of the 67 workmen and their families who lived nearby. St. Francis Dam_sentence_157

This cut power to much of Los Angeles and the San Fernando Valley. St. Francis Dam_sentence_158

It was quickly restored via tie-lines with Southern California Edison Company, but as the floodwater entered the Santa Clara riverbed it overflowed the river's banks, flooding parts of present-day Valencia and Newhall. St. Francis Dam_sentence_159

At about 12:40 a.m. Southern California Edison's two main lines into the city were destroyed by the flooding, re-darkening the areas that had earlier lost power, and spreading the outage to other areas served by Southern California Edison. St. Francis Dam_sentence_160

Nonetheless power to most of the areas not flooded was restored with power from Edison's Long Beach steam electric generating plant. St. Francis Dam_sentence_161

Near 1:00 a.m. the mass of water, then 55 ft (17 m) high, followed the river bed west and demolished Edison's Saugus substation, cutting power to the entire Santa Clara River Valley and parts of Ventura and Oxnard. St. Francis Dam_sentence_162

At least four miles of the state's main north–south highway was under water and the town of Castaic Junction was being washed away. St. Francis Dam_sentence_163

The flood entered the Santa Clarita valley at 12 mph (19 km/h). St. Francis Dam_sentence_164

Approximately five miles downstream, near the Ventura–Los Angeles county line, a temporary construction camp the Edison Company had set up for its 150-man crew on the flats of the river bank was hit. St. Francis Dam_sentence_165

In the confusion, Edison personnel had been unable to issue a warning and 84 workers perished. St. Francis Dam_sentence_166

Shortly before 1:30 a.m., a Santa Clara River Valley telephone operator learned from the Pacific Long Distance Telephone Company that the dam had failed. St. Francis Dam_sentence_167

She called a California Highway Patrol officer, then began calling the homes of those in danger. St. Francis Dam_sentence_168

The CHP officer went from door to door warning residents about the imminent flood. St. Francis Dam_sentence_169

At the same time, a deputy sheriff drove up the river valley, toward the flood, with his siren blaring, until he had to stop at Fillmore. St. Francis Dam_sentence_170

The flood heavily damaged the towns of Fillmore, Bardsdale, and Santa Paula, before emptying both victims and debris into the Pacific Ocean 54 miles (87 km) downstream south of Ventura at what is now the West Montalvo Oil Field around 5:30 a.m., at which point the wave was almost two miles (3 km) wide and still traveling at 6 mph (9.7 km/h). St. Francis Dam_sentence_171

Newspapers across the country carried accounts of the disaster. St. Francis Dam_sentence_172

The front page of the Los Angeles Times ran four stories, including aerial photos of the collapsed dam and the city of Santa Paula. St. Francis Dam_sentence_173

A Times Flood Relief Fund was set up to receive donations, mirrored by similar efforts by other publications. St. Francis Dam_sentence_174

In a statement Mulholland said, "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 2:30 a.m. this morning. St. Francis Dam_sentence_175

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." St. Francis Dam_sentence_176

Mulholland stated that it appeared that there had been major movement in the hills forming the western buttress of the dam, adding 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. St. Francis Dam_sentence_177

It was noted that no tremors had been reported at seismograph stations, ruling out an earthquake as the cause of the break. St. Francis Dam_sentence_178

Investigation St. Francis Dam_section_4

There were at least a dozen separate investigations into the collapse. St. Francis Dam_sentence_179

With unprecedented speed, eight of these had begun by the weekend following the collapse. St. Francis Dam_sentence_180

Almost all of these involved investigative panels of prominent engineers and geologists. St. Francis Dam_sentence_181

The more notable of these groups and committees were those sponsored by California governor C. St. Francis Dam_sentence_182 C. Young, headed by A. J. Wiley, the renowned dam engineer and consultant to the U.S. St. Francis Dam_sentence_183 Bureau of Reclamation's Boulder (Hoover) Dam Board; the Los Angeles City Council, which was chaired by the Chief of the Reclamation Service, Elwood Mead; the Los Angeles County coroner, Frank Nance and Los Angeles County District Attorney Asa Keyes. St. Francis Dam_sentence_184

Others were convened: the Water and Power Commissioners started their own inquiry, as did the Los Angeles County Board of Supervisors who hired J. B. Lippincott. St. Francis Dam_sentence_185

The Santa Clara River Protective Association employed the geologist and Stanford University professor emeritus, Dr. Bailey Willis, and eminent San Francisco Civil Engineer and past president of the American Society of Civil Engineers, Carl E. Grunsky. St. Francis Dam_sentence_186

There were others, such as the railroad commission and several political entities who only sent investigators or representatives. St. Francis Dam_sentence_187

Although they were not unanimous on all points, most commissions quickly reached their respective conclusions. St. Francis Dam_sentence_188

The governor's commission met on March 19 and submitted their 79-page report to the governor on March 24, five days later, and only eleven days after the early-morning March 13 flood. St. Francis Dam_sentence_189

Although this may have been sufficient time to answer what they had been directed to determine, they had been deprived of the sworn testimony at the Coroner's Inquest which was scheduled to be convened March 21, the only inquiry that took into consideration factors other than geology and engineering. St. Francis Dam_sentence_190

The need for nearly immediate answers was understandable, having its roots in the SwingJohnson Bill in Congress. St. Francis Dam_sentence_191

This bill, which had first been filed in 1922, and failed to be voted on in three successive Congresses, was again before Congress at the time. St. Francis Dam_sentence_192

This bill ultimately provided the funding for constructing the Hoover Dam. St. Francis Dam_sentence_193

Supporters and responsible leaders alike realized the jeopardy in which the bill then stood. St. Francis Dam_sentence_194

Although the water and electricity from the project were needed, the idea of the construction of such a massive dam of similar design, which would create a reservoir seven hundred times larger than the St. Francis, did not sit well with many in light of the recent disaster and the devastation. St. Francis Dam_sentence_195

The bill was passed by Congress, and signed into law by President Coolidge on December 21, 1928. St. Francis Dam_sentence_196

The governor's commission was the first to release its findings, titled Report of the Commission appointed by Governor C. C. Young to investigate the causes leading to the failure of the St. Francis dam near Saugus, California. St. Francis Dam_sentence_197

The report became the most widely distributed analysis. St. Francis Dam_sentence_198

Along with most of the other investigators, they perceived the new leak as the key to understanding the collapse, although the commission believed that "the foundation under the entire dam left very much to be desired." St. Francis Dam_sentence_199

The report stated, "With such a formation, the ultimate failure of this dam was inevitable, unless water could have been kept from reaching the foundation. St. Francis Dam_sentence_200

Inspection galleries, pressure grouting, drainage wells and deep cut-off walls are commonly used to prevent or remove percolation, but it is improbable that any or all of these devices would have been adequately effective, though they would have ameliorated the conditions and postponed the final failure." St. Francis Dam_sentence_201

They placed the cause of the failure on the western hillside. St. Francis Dam_sentence_202

"The west end," the commission stated, "was founded upon a reddish conglomerate which, even when dry, was of decidedly inferior strength and which, when wet, became so soft that most of it lost almost all rock characteristics." St. Francis Dam_sentence_203

The softening of the "reddish conglomerate" undermined the west side. St. Francis Dam_sentence_204

"The rush of water released by failure of the west end caused a heavy scour against the easterly canyon wall ... and caused the failure of that part of the structure." St. Francis Dam_sentence_205

There then "quickly followed ... the collapse of large sections of the dam." St. Francis Dam_sentence_206

The committee appointed by the Los Angeles City Council, for the most part concurred in attributing the collapse to "defective foundations", and wrote, "The manner of failure was that the first leak, however started, began under the concrete at that part of the dam which stood on the red conglomerate; this leak increased in volume as it scoured away the foundation material already greatly softened by infiltrated water from the reservoir which removed the support of the dam at this point and since no arch action could occur by reason of the yielding conglomerate abutment, made failure of the dam inevitable." St. Francis Dam_sentence_207

Likewise, they concluded the failure most likely followed a pattern similar to that which was proposed by the governor's commission, although they did acknowledge that "the sequence of failure is uncertain." St. Francis Dam_sentence_208

The committee ended their report with, "...having examined all the evidence which it has been able to obtain to date reports its conclusions as follows: St. Francis Dam_sentence_209

St. Francis Dam_ordered_list_0

  1. The type and dimensions of the dam were amply sufficient if based on suitable foundation.St. Francis Dam_item_0_0
  2. The concrete of which the dam was built was of ample strength to resist the stresses to which it would normally be subjected.St. Francis Dam_item_0_1
  3. The failure cannot be laid to movement of the earth's crust.St. Francis Dam_item_0_2
  4. The dam failed as a result of defective foundations.St. Francis Dam_item_0_3
  5. This failure reflects in no way the stability of a well designed gravity dam properly founded on suitable bedrock."St. Francis Dam_item_0_4

The consensus of most of the investigating commissions was that the initial break had taken place at or near the fault line on the western abutment, which had been a problem area since water first covered the area. St. Francis Dam_sentence_210

The prevailing thought was that increasing water percolation through the fault line had either undermined or weakened the foundation to a point that a portion of the structure blew out or the dam collapsed from its own immense weight. St. Francis Dam_sentence_211

This was supported by a chart made by the automatic water level recorder located on the dam's center section. St. Francis Dam_sentence_212

This chart clearly showed that there had been no significant change in the reservoir level until forty minutes before the dam's failure, at which time a small though gradually increasing loss was recorded. St. Francis Dam_sentence_213

This controversial item, unfortunately, turned out to be another area in which the investigating bodies were handicapped from lacking the information that was later brought to light in the testimony at the Coroner's Inquest, which was the only investigation that took evidence other than engineering and geology into account. St. Francis Dam_sentence_214

The only theory to vary greatly from the others was that of Bailey Willis, Carl E. Grunsky and his son. St. Francis Dam_sentence_215

They believed that the portion of the east abutment below the dam was the first to give way, clearing the way for the collapse to take place. St. Francis Dam_sentence_216

Their investigations, while somewhat collaborative, culminated in two separate reports (one by the Grunskys and the other by Dr. Willis) which were completed in April 1928. St. Francis Dam_sentence_217

These reports, according to Carl Grunsky, "were reached independently" and "are in substantial agreement." St. Francis Dam_sentence_218

Dr. Willis and the Grunskys agreed with the other engineers and investigators about the poor quality and deteriorating conditions of the entire foundation, although they maintained that a critical situation developed on the east abutment. St. Francis Dam_sentence_219

Dr. Willis, the geologist of the investigative team, was most likely the first to discover the "old landslide" within the mountains which had made the eastern abutment for the dam. St. Francis Dam_sentence_220

In his report, he discussed it at great length and the Grunskys drew substantially on it, as they did his analysis of the schist, for their own report. St. Francis Dam_sentence_221

The Grunskys, as civil engineers, took the lead in that area of the investigation, and in describing the role played by "hydrostatic uplift". St. Francis Dam_sentence_222

Uplift takes its name from its tendency to lift a dam upward. St. Francis Dam_sentence_223

Although many designers and builders of dams had become aware of this phenomenon by the late 1890s to early 1900s, it was still not generally well understood or appreciated. St. Francis Dam_sentence_224

Nevertheless, it was becoming a matter of debate and a concern to dam builders of this era that water from a reservoir could seep under a dam and exert pressure upward. St. Francis Dam_sentence_225

Due for the most part to inadequate drainage of the base and side abutments, the phenomenon of uplift destabilizes gravity dams by reducing the structure's "effective weight", making it less able to resist horizontal water pressure. St. Francis Dam_sentence_226

Uplift can act through the bedrock foundation: the condition most commonly develops where the bedrock foundation is strong enough to bear the weight of the dam, but is fractured or fissured and therefore susceptible to seepage and water saturation. St. Francis Dam_sentence_227

According to their theories, water from the reservoir had permeated far back into the schist formation of the eastern abutment. St. Francis Dam_sentence_228

This lubricated the rock and it slowly began to move, exerting a tremendous amount of weight against the dam, which according to the Grunskys was already becoming less stable due to "uplift". St. Francis Dam_sentence_229

Making the situation worse, Dr. Willis established, was that the conglomerate, on which the western abutment of the dam rested, reacted upon becoming wet by swelling. St. Francis Dam_sentence_230

In fact, the amount of swelling was such that it would raise any structure built upon it. St. Francis Dam_sentence_231

This hypothesis was reinforced when surveys taken of the wing wall after the failure were compared with those taken at the time it was built. St. Francis Dam_sentence_232

They reveal that in some areas the wall was 2 to 6 inches higher than when built. St. Francis Dam_sentence_233

Therefore, the dam was caught between forces that were acting on it much like a vise, as the red conglomerate swelled on one side, and the moving mountain pressed in on it from the other. St. Francis Dam_sentence_234

In his report, Grunsky concluded: St. Francis Dam_sentence_235

There was and remains a difference of professional opinions on the amount of time that elapsed, shown by the chart made by the Stevens automatic water level recorder, from when the line indicating the reservoir level broke sharply downward until it became perpendicular. St. Francis Dam_sentence_236

Most investigating engineers feel the amount of time indicated on the chart is thirty to forty minutes, not the twenty-three minutes that Grunsky stated. St. Francis Dam_sentence_237

In support of his theory of the dam tilting, Grunsky pointed to an odd clue near the western lower edge of the standing section. St. Francis Dam_sentence_238

Here a ladder had become wedged in a crack that had opened apparently during this rocking or tilting process and then had become tightly pinched in place as the section settled back on its foundation. St. Francis Dam_sentence_239

Measurements taken proved the crack must have been much wider at the time that the ladder entered it. St. Francis Dam_sentence_240

Further, surveys indeed showed the center section had been subjected to severe tilting or twisting. St. Francis Dam_sentence_241

These surveys established that the center section had moved 5.5 inches (14 cm) downstream and 6 inches (15 cm) toward the eastern abutment. St. Francis Dam_sentence_242

Although this investigation was insightful and informative, the theory, along with others which hypothesized an appreciably increasing amount of seepage just prior to the failure, becomes less likely when it is compared against the eyewitness accounts of the conditions in the canyon and near the dam during the last thirty minutes before its collapse. St. Francis Dam_sentence_243

Grunsky hypothesized, though failed to explain, the action of the dam tilting as he described. St. Francis Dam_sentence_244

This action would have the dam in motion as a singular unit while conversely, testimony given at the Coroner's Inquest indicates that the dam was fractured transversely in at least four places. St. Francis Dam_sentence_245

Furthermore, the two cracks, which bordered each side of the standing center section, would have served as hinges to prevent this. St. Francis Dam_sentence_246

Aftermath St. Francis Dam_section_5

The center section, which had become known as "The Tombstone" due to a newspaper reporter's description of it as such, became an attraction for tourists and souvenir hunters. St. Francis Dam_sentence_247

In May 1929, the upright section was toppled with dynamite, and the remaining blocks were demolished with bulldozers and jackhammers to discourage the sightseers and souvenir hunters from exploring the ruins. St. Francis Dam_sentence_248

The wing dike was used by Los Angeles firemen to gain experience in using explosives on building structures. St. Francis Dam_sentence_249

The St. Francis Dam was not rebuilt, though Bouquet Reservoir in nearby Bouquet Canyon was built in 1934 as a replacement. St. Francis Dam_sentence_250

The exact number of victims remains unknown. St. Francis Dam_sentence_251

The official death toll in August 1928 was 385, but the remains of victims continued to be discovered every few years until the mid-1950s. St. Francis Dam_sentence_252

Many victims were swept out to sea when the flood reached the Pacific Ocean and were never recovered, while others were washed ashore, some as far south as the Mexican border. St. Francis Dam_sentence_253

The remains of one victim were found deep underground near Newhall in 1992, and other bodies, believed to be victims of the disaster, were found in the late 1970s and 1994. St. Francis Dam_sentence_254

The death toll is currently estimated to be at least 431. St. Francis Dam_sentence_255

At the Coroner's Inquest, the leak that Tony Harnischfeger had spotted was cited as evidence that the dam was leaking on the day of the break, and that both the Bureau of Water Works and Supply and Mulholland were aware of it. St. Francis Dam_sentence_256

Mulholland told the jury he had been at the dam the day of the break, due to the dam keeper's call, but neither he nor Van Norman had observed anything of concern, nor found any dangerous conditions. St. Francis Dam_sentence_257

Mulholland further testified that leaks in dams, especially of the type and size of the St. Francis, were common. St. Francis Dam_sentence_258

During the Inquest Mulholland said, "This inquest is a very painful thing for me to have to attend but it is the occasion of it that is painful. St. Francis Dam_sentence_259

The only ones I envy about this thing are the ones who are dead." St. Francis Dam_sentence_260

In subsequent testimony, after answering a question he added, "Whether it is good or bad, don't blame anyone else, you just fasten it on me. St. Francis Dam_sentence_261

If there was an error in human judgment, I was the human, I won't try to fasten it on anyone else." St. Francis Dam_sentence_262

The Coroner's Inquest jury determined that one of the causative factors for the disaster lay in what they had termed as "an error in engineering judgment in determining the foundation at the St. Francis Dam site and deciding on the best type of dam to build there" and that "the responsibility for the error in engineering judgment rests upon the Bureau of Water Works and Supply, and the Chief Engineer thereof." St. Francis Dam_sentence_263

They cleared Mulholland as well as others of the Bureau of Water Works and Supply of any criminal culpability, since neither he nor anyone else at the time could have known of the instability of the rock formations on which the dam was built. St. Francis Dam_sentence_264

The hearings also recommended that "the construction and operation of a great dam should never be left to the sole judgment of one man, no matter how eminent." St. Francis Dam_sentence_265

Mulholland retired from the Bureau of Water Works and Supply December 1, 1928. St. Francis Dam_sentence_266

His assistant, Harvey Van Norman, succeeded him as chief engineer and general manager. St. Francis Dam_sentence_267

Mulholland was retained as Chief Consulting Engineer, with an office, and received a salary of $500 a month. St. Francis Dam_sentence_268

In later years, he retreated into a life of semi-isolation. St. Francis Dam_sentence_269

He died in 1935, at the age of 79. St. Francis Dam_sentence_270

Dam safety legislation St. Francis Dam_section_6

In response to the St. Francis Dam disaster, the California legislature created an updated dam safety program and eliminated the municipal exemption. St. Francis Dam_sentence_271

Before this was added, a municipality having its own engineering department was completely exempt from regulation. St. Francis Dam_sentence_272

On August 14, 1929, the Department of Public Works, under the administrative oversight of the State Engineer, which was later assumed by the Division of Safety of Dams, was given authority to review all non-federal dams over 25 feet high or which could hold more than 50 acre-feet of water. St. Francis Dam_sentence_273

The new legislation also allowed the state to employ consultants, as they deemed necessary. St. Francis Dam_sentence_274

Additionally, the state was given full authority to supervise the maintenance and operation of all non-federal dams. St. Francis Dam_sentence_275

Licensure of civil engineers St. Francis Dam_section_7

Having determined that the unregulated design of construction projects constituted a hazard to the public, the California legislature passed laws to regulate civil engineering and, in 1929, created the state Board of Registration for Civil Engineers (now the Board for Professional Engineers, Land Surveyors, and Geologists). St. Francis Dam_sentence_276

Analysis St. Francis Dam_section_8

The failure of the dam is now believed to have begun with the eastern abutment of the dam giving way, possibly due to a landslide. St. Francis Dam_sentence_277

This scenario, having its roots in the works of Willis and Grunsky, was expanded upon by the author Charles Outland in his book Man-Made Disaster : The Story of St. Francis Dam which was first published in 1963. St. Francis Dam_sentence_278

The material on which the eastern abutment of the dam had been built may itself have been part of an ancient landslide, but this would have been impossible for almost any geologists of the 1920s to detect. St. Francis Dam_sentence_279

Indeed, the site had been inspected twice, at different times, by two of the leading geologists and civil engineers of the day, John C. Branner of Stanford University and Carl E. Grunsky; neither found fault with the San Francisquito rock. St. Francis Dam_sentence_280

J. David Rogers, inspired by the work of Outland, investigated the failure and published an extensive scenario, albeit somewhat controversial, of the possible geological and rock mechanic actions which may have led to the dam's failure. St. Francis Dam_sentence_281

He attributed the failure to three major factors: the instability of the ancient landslide material on which the dam was built, the failure to compensate for the additional height added to the dam's design, and the design and construction being overseen by only one person. St. Francis Dam_sentence_282

A critique of Rogers's historical analysis of the dam's collapse was published in the journal California History in 2004 by historians Norris Hundley Jr. (Professor Emeritus, UCLA) and Donald C. Jackson (Professor, Lafayette College). St. Francis Dam_sentence_283

While accepting most of his geological analysis of the failure, the article makes clearer the differences and deficiencies of the structure built in San Francisquito Canyon and how it fell short of the standards for large-scale concrete gravity dams as practiced by other prominent dam engineers in the 1920s. St. Francis Dam_sentence_284

Mulholland Dam reinforcement St. Francis Dam_section_9

Shortly after the disaster, many living below Mulholland Dam, which creates the Hollywood Reservoir, feared a similar disaster and began to protest, and petitioned the City of Los Angeles to drain the reservoir and remove the dam. St. Francis Dam_sentence_285

A Committee of Engineers & Geologists to Assess Mulholland Dam was appointed to evaluate the dam's safety. St. Francis Dam_sentence_286

An External Review Panel to evaluate the structure, convened by the State of California, followed in 1930. St. Francis Dam_sentence_287

The same year, the City of Los Angeles Board of Water & Power Commissioners appointed their own Board of Review for the dam. St. Francis Dam_sentence_288

Although the state's panel did not recommend modification of the dam, both panels came to similar conclusions: that the dam lacked what was then considered sufficient uplift relief, which could lead to destabilization, and was unacceptable. St. Francis Dam_sentence_289

Again in 1931, a fourth panel, the Board of Engineers to Evaluate Mulholland Dam, was appointed to assess the structure. St. Francis Dam_sentence_290

As well, an external study group appointed by the Board of Water & Power Commissioners produced a "Geological Report of the Suitability of Foundations". St. Francis Dam_sentence_291

Certain design deficiencies were uncovered in the plans made by the engineering department during the planning phase of the dam. St. Francis Dam_sentence_292

These had to do with the dam's base width in conjunction to its ability to resist uplift and sliding and to withstand earthquake loading. St. Francis Dam_sentence_293

The decision was made to permanently keep the Hollywood Reservoir drawn down. St. Francis Dam_sentence_294

It was also decided to keep the amount stored in the reservoir to no more than 4,000 acre⋅ft (4,900,000 m) and to place an enormous amount of earth, 330,000 cu yd (250,000 m), on the dam's downstream face to increase its resistance against hydraulic uplift and earthquake forces, and to screen it from public view. St. Francis Dam_sentence_295

This work was carried out in 1933–34. St. Francis Dam_sentence_296

Legacy St. Francis Dam_section_10

The only visible remains of the St. Francis Dam are weathered, broken chunks of gray concrete and the rusted remnants of the handrails that lined the top of the dam and the wing dike. St. Francis Dam_sentence_297

The ruins and the scar from the ancient landslide can be seen from San Francisquito Canyon Road. St. Francis Dam_sentence_298

Large chunks of debris can still be found scattered about the creek bed south of the dam's original site. St. Francis Dam_sentence_299

The site of the disaster is registered as California Historical Landmark #919. St. Francis Dam_sentence_300

The landmark is located on the grounds of Powerhouse No. St. Francis Dam_sentence_301

2 and is near San Francisquito Canyon Road. St. Francis Dam_sentence_302

The marker reads: St. Francis Dam_sentence_303

San Francisquito Canyon Road sustained heavy storm damage in 2005, and when rebuilt in 2009, it was re-routed away from the original road bed and the remains of the main section of the dam. St. Francis Dam_sentence_304

The new road is routed through a cut which was made in the hillside on the western edge of the wing dike. St. Francis Dam_sentence_305

National Monument and National Memorial St. Francis Dam_section_11

The John D. Dingell, Jr. Conservation, Management, and Recreation Act, signed March 12, 2019, authorized the establishment of the Saint Francis Dam Disaster National Memorial and established the Saint Francis Dam Disaster National Monument. St. Francis Dam_sentence_306

The sites are administered by the United States Forest Service within Angeles National Forest to commemorate the collapse of the dam and preserve 353 acres (143 ha) of land for recreation and protection of resources. St. Francis Dam_sentence_307

The is a 501c3 non-profit organization, established in 2019, with the goal of raising funds to support the United States Forest Service in building and maintaining the St. Francis Dam Disaster National Memorial and Monument, including the construction of a visitor's center and memorial wall with the names of all the victims. St. Francis Dam_sentence_308

In popular culture St. Francis Dam_section_12

St. Francis Dam_unordered_list_1

  • Numerous fictionalized references are made to Mulholland, the California Water Wars, the aqueduct, and the St. Francis Dam disaster in the 1974 movie Chinatown.St. Francis Dam_item_1_5
  • Rock musician Frank Black makes several references to the St. Francis Dam disaster in his songs "St. Francis Dam Disaster" and "Olé Mulholland."St. Francis Dam_item_1_6
  • The 2014 young adult novel 100 Sideways Miles by Andrew A. Smith features the current site of the dam disaster as well as some discussion of the historical event.St. Francis Dam_item_1_7
  • The rise of William Mulholland, Los Angeles' water issues, and the collapse of the dam is told in the 2018 documentary, Forgotten Tragedy: The Story of The St Francis Dam by Jesse Cash.St. Francis Dam_item_1_8
  • A new musical in development about the rise of Los Angeles resulting from the delivery of water from the Owens Valley, Locals produce musical remembering St. Francis Dam disaster by Emily Alvarenga.St. Francis Dam_item_1_9

See also St. Francis Dam_section_13

St. Francis Dam_unordered_list_2


Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/St. Francis Dam.