who was president when the hoover dam was built
Franklin D. Roosevelt.
Introduction
 It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt.
Franklin D. Roosevelt President Franklin D. Roosevelt President Franklin D. Roosevelt.
Hoover Dam Hoover Dam Hoover Dam
Introduction Dedication and completion Introduction
 It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt. With most work finished on the dam itself (the powerhouse remained uncompleted), a formal dedication ceremony was arranged for September 30, 1935, to coincide with a western tour being made by President Franklin D. Roosevelt.  It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt.
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Hoover Dam [SEP] Introduction
Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Nevada and Arizona. It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt. Its construction was the result of a massive effort involving thousands of workers, and cost over one hundred lives. Originally known as Boulder Dam from 1933, it was officially renamed Hoover Dam for President Herbert Hoover by a joint resolution of Congress in 1947. Since about 1900, the Black Canyon and nearby Boulder Canyon had been investigated for their potential to support a dam that would control floods, provide irrigation water and produce hydroelectric power.