The penstock pipes for the original two units at Big Creek Power Houses One and Two, built 1912-13, were purchased from the Krupp Works in Germany because at that time that manufacturer produced steel pipes of the tensile strength needed to contain the very high water pressures in the pipes in the 1500 foot drop down to Power House One.
If water level then drops, it may lower below the penstock openings, which are higher up on the dam face, then the release capacity of the dam drops to zero, and the Colorado River below the dam could remain dry until the next major spring inflow, and only springs, seeps and tributaries such as the Paria, Little Colorado and Virgin River would replenish its flow during these times, perhaps causing unprecedented drops in levels of Lake Mead as well.
The water then enters a penstock that feeds the Camino Powerhouse above Slab Creek Reservoir on the South Fork American River.