#colorado-river-basin

#colorado-river-basin

If the lake level drops below 3,490 feet - termed the minimum power pool - the turbines that generate electricity have to be shut down. When the water level reaches critically low thresholds, air is sucked down like a whirlpool into the penstocks, forming explosive bubbles which can cause massive failure inside the dam.

"The numbers are really, really bad," Swain says. "If this were November, they might be less meaningful. We're not in November-we're heading toward mid-February. The normal numbers are pretty high. To be at half of them means that, in absolute terms, the deficit is large."