| Construction of the dam at Hetch Hetchy began almost immediately after President Woodrow Wilson signed the Raker Bill into law. The valley floor was cleared of all timber, roads and railroads were constructed into the valley, the dam site at the mouth of the valley was blasted back to bedrock, the process of pouring layer upon layer of concrete commenced, tunnels for the pipeline to the San Francisco Bay area drilled, and construction of power plants begun. Initial construction took nine years. Dedication of O'Shaughnessey Dam - named after the city's and the project's chief engineer, Michael O'Shaughnessey - took place on July 7, 1923. |
