Technology and Culture

In the wee hours of 13 March 1928, one of the nation's greatest engineering disasters killed some 400 people when the St. Francis Dam collapsed, unleashing a devastating, 12 billion-gallon torrent into the Santa Clara River. Thirty years later, when I was growing up in that part of Southern California, old-timers would recount harrowing stories of that tragic event, stirring my youthful imagination and sparking a lasting curiosity about the interplay of technology and the environment.

In their exhaustively researched book, Heavy Ground, Norris Hundley and D. C. Jackson offer a gripping account of this ill-fated dam and the person most directly responsible for its flawed design: William Mulholland, the self-taught chief engineer of Los Angeles's municipal water system. Historians of technology will find much to emulate in this Sally Hacker Prize-winning book, including its exemplary use of images to amplify—rather than merely illustrate—the text. Hundley and Jackson also do a commendable job of parsing the interwoven roles of politics and engineering when assessing why the St. Francis Dam failed. The project's sole purpose was to create an additional storage reservoir for the Sierra Nevada meltwater being channeled over 200 miles from the Owens Valley via the Los Angeles Aqueduct, completed in 1913. Ease of land acquisition rather than favorable geological conditions led Mulholland to site the dam in San Francisquito Canyon, within the upper Santa Clara River watershed.

Because California law allowed municipalities with engineering departments to design and build dams without state review and approval, Mulholland was within his right to operate without external oversight. His decision to go it alone, however, without following the common practice of engaging consulting engineers, bordered on culpable negligence, given his lack of experience with concrete gravity dam construction. Hundley and Jackson explain how this arrogance led Mulholland to discount the destabilizing threat of "uplift," which occurs when pressurized water seeps under a structure, lessening its weight. His decision to build the St. Francis Dam without pressure grouting the foundation or incorporating a cutoff trench, drainage wells, or an inspection tunnel within the dam's interior (elements that would have substantially reduced seepage and uplift) was a design oversight that ran contrary to the best engineering practices of the day. Also questionable was Mulholland's decision to enlarge the reservoir capacity by raising the height of the dam during mid-construction, but without proportionately expanding the dam's structural base, which would be needed to withstand the increased hydrostatic pressure.

In the aftermath of the tragedy, some change did occur, for both good [End Page 798] and ill. Political factors associated with the impending Boulder Canyon Project Act influenced investigations into the St. Francis Dam's collapse, leading politicians and engineers to avoid criticizing gravity dam technology (which was the method to be employed by the proposed Boulder—later Hoover—Dam). The tragedy did, however, prompt California to revise its dam safety regulations by eliminating the municipal exemption for state inspection and approval.

In their conclusion, the authors highlight the intersecting nature of technology, culture, and politics. Technology, they remind us, "is not a force operating in isolation from the society that produces and sustains it. Technology and culture are inextricably intertwined, a connection we often wish to deny, or at least ignore." As this history demonstrates, the dam itself was "the product of human culture, one that allowed William Mulholland enormous freedom in selecting the dam's location, creating its design, and building it without outside review or interference" (p. 322), with disastrous consequences for those who lived, and died, downriver.