The major construction project that took place between 1929 and 1938 in the U.S. was the construction of the Hoover Dam. Located on the Colorado River, it was built during the Great Depression as part of efforts to create jobs and stimulate the economy. The dam provided vital irrigation, flood control, and hydroelectric power to the southwestern U.S. It was an engineering marvel of its time, showcasing advancements in construction techniques and serving as a symbol of recovery and strength during a challenging economic period.