The warning is contained in a report obtained Wednesday by The Associated Press. It was made by a federally created investigating team for Oroville dam.
VIDEO: Oroville Dam emergency spillway at risk of failing
It says repair crews at the Lake Oroville dam have only a few months to make sure the spillway is in good enough shape for the next rainy season, which starts in November, or the state faces a "very significant risk."
The report does not specify the risk.
Authorities evacuated nearly 200,000 people last month after huge holes appeared in both the main spillway and emergency spillway. Officials are worried the hole in the main spillway could get bigger.
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