“The largest uncontested achievement of Hoover’s leadership is the one that still bears his name: the Hoover Dam. By the time he got back to America, the plan to dam the Colorado River and thereby irrigate and power California’s Los Angeles “Southland” already existed, but it took an organizer of Hoover’s skill to bring several state and municipal governments, federal agencies, and private firms into agreement on how to divide such a massive bounty.
From the book Palo Alto by Malcolm Harris
He needed the entire length of his Commerce terms, but the Chief finally got the damn dam built in his image. First he got representatives from the affected states into a room and hammered out the Colorado River Compact over the course of two weeks. The interstate accord set the future direction of the river, but it was a stacked deck, because the congressional (Senate and House) as well as White House representatives all came from California.”
See this article on the controversy about naming Hoover Dam. A change in administration from one party to the other while the dam was being constructed provided the opportunity to reconsider its name!
When President Roosevelt dedicated the dam in 1935, he too called it Boulder Dam.
Truman later resolved the matter in favor of Hoover:
…on April 30, 1947, President Harry Truman signed Public Law 43 which read: “Resolved … that the name of Hoover Dam is hereby restored to the dam on the Colorado River in Black Canyon constructed under the authority of the Boulder Canyon Project Act…
For more on Hoover Dam and its history, see this page on the National Archives website for the Herbert Hoover Presidential Library and Museum.