Construction of the Intake Structure took 5 years and cost $21 million in 1954. Enough concrete to pave a road 115 miles long was used to build it. The Intake Structure is 249 feet tall, 540 feet long, and 170 feet wide. It houses the hoisting equipment, gates, and auxiliary equipment for five penstocks and three regulatory tunnels. Each penstock is 24 feet in diameter and conveys water to turbines for power generation, while the three regulatory tunnels send water downstream for flood control. The penstocks carry water from the intake to the scroll case around the turbine. Water moves through the penstocks at a rate of 60,000 gallons per second and at a speed of 12 to 13 miles per hour.