Over 200 feet below the water surface of a full Don Pedro Lake is the old Don Pedro Dam. It was submerged when the new, larger earth-fill dam construction was completed 1.5 miles downstream in 1971.
About this Establishment
The old Don Pedro Dam construction was completed in 1923. Built and owned by the Turlock Irrigation District and the Modesto Irrigation District, the dam not only allowed a 1923 irrigation season's worth of water to be stored (289,000 acre feet), it powered electricity for the cities of Modesto and Turlock. At 284' tall, the arched concrete structure was the tallest dam in the world at the time. It was 177' thick at its base, 16' wide at its top, and 1,000' long across the top of the dam.