John E. Raker was a Representative from San Francisco who first proposed the bill. The bill was presented in front of the Sixty-third Congress to approve the grant to dam the valley. When he appeared in front of Congress, he was the one who first brought up the point that while the valley remained a valley it was a "barren wasteland" but if it was transformed into a dam its worth would rise $3 million. He was one of the proponents that was strongly sided with the damming and didn't have any reluctance towards his decision.
John E. Raker source: Bay Area Water Supply and Conservation Agency