Newspaper: Oroville Dam's flood-control manual out of date

A trail runs along the Feather River as water gushes from the Oroville Dam's main spillway Wednesday, Feb. 15, 2017, in Oroville, Calif. The Oroville Reservoir is continuing to drain Wednesday as state water officials scrambled to reduce the lake's level ahead of impending storms. (AP Photo/Marcio Jose Sanchez)

OROVILLE, Calif. (AP) — The critical document that determines how much space should be left in Lake Oroville for flood control during the rainy season hasn't been updated in 47 years.

The Sacramento Bee reports ( ) the outdated document uses climatological data and runoff projections that don't account for two past floods.

Independent experts familiar with the flood-control manual at Oroville Dam say there's no indication the outdated document contributed to the ongoing crisis involving the dam's ailing spillways. Structural failures are the trouble.

But experts say the manual points to larger operational issues that affect most of California's primary flood-control dams.

Last week, the Department of Water Resources discovered a massive crater in the concrete-lined spillway.

Later, the emergency spillway was used. But erosion began to progress up the right side, prompting authorities to order an evacuation of 188,000 people.