The text provides a detailed account of the Hetch‑Hetchy valley and its Tuolumne watershed, traces the long municipal campaign to secure a mountain water and power supply, and explains the provisions and passage of the Raker Bill enabling reservoir and hydroelectric development. It evaluates engineering plans, legal claims and administrative arrangements, outlines expected benefits for San Francisco, Bay counties and irrigation districts, and examines likely effects on Yosemite National Park, regional irrigation and long‑term resource management.