Monday, 31 July 2017

Danger looms at California's Oroville Dam

Last winter's epic rainfall brought the Oroville Dam, the country's tallest embankment dam and a crucial reservoir in California's beleaguered water supply system, near an epic collapse. Tens of thousands were evacuated as decision-making worsened the situation and an emergency spillway began to crumble. Now, one of the team leads studying the dam says more trouble is looming...

A 15-member team at UC Berkeley, through the university's Center for Catastrophic Risk Management, issued the report earlier this month, and one of the team leads, professor emeritus Robert Bea, tells SFGate that the state Department of Water Resources (DWR) has been disingenuous in their public lack of concern over some patches of green vegetation that have appeared partway down the earthen dam which could be signs of slow water seepage that could lead to the dam's ultimate failure.

According to the report, "Oroville Dam may be facing a breach danger from a serious and a dangerous form of a slow motion failure mode of the left abutment of the dam."

The green spots, which the report points out have appeared in both rainy and drought years, are the result of a "natural spring" according to the DWR. But why, then, did the DWR conduct some sort of drill test near the green spots in 2016 if they aren't concerned about them.

Via SFist

(Image via Robert Bea/SFist)