Nation's biggest dam overflows into emergency spillway for first time in 50 years

California has spent the last six years grappling with a brutal drought. Now parts of the Golden State are suffering from the opposite problem: too much water.

Extreme flooding this weekend washed away chunks of highway, derailed trains and inundated homes in Northern California. At Lake Oroville, a major man-made reservoir, water began flowing over a never-before-used emergency spillway at the Oroville Dam.

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The 770-foot-tall dam — the tallest in the country — lies about 150 miles northeast of San Francisco. Opened in 1968, the colossal infrastructure supplies water for farms in the Central Valley and homes and buildings in Southern California. Read more...

More about San Francisco, Bay Area, Floods, Flooding, and Rainfall