The Oroville dam spillway that crumbled under intense pressure from use this rainy season, precipitating area evacuations that were only fully lifted this week, has work crews rushing to reconstruct the structure. If they don't finish the job by the beginning of the next rainy season, a team of safety experts warns in a report obtained by the Associated Press, the potential risks could be "very significant."

For the spillway to be operational by next fall, the state must execute its reconstruction plan without any time allotted for delays. Contracts must be awarded by June, and workers will aim to have the spillway in shape by November 1. A full repair will take up to two years according to consultants, and still two months remain in the current wet season, with unusually significant Sierra snowpack to send runoff into Lake Oroville as temperatures rise.

"This is a very demanding schedule, as everyone recognizes," write the five safety experts who authored the report. "There seems to be no room anywhere to expand any part of the schedule." But the report's warning of "very significant" risk is somewhat inscrutable to the AP, as is the declaration that it's "absolutely critical" for the dam's state operators not to use the current, faulty emergency spillway again. Instead, a new spillway is called for, the experts insist.

The reconstruction effort calls to mind the original push to build the dam, which is the tallest in the nation. Though many of the original builders of the Oroville Dam have passed away, a few, including John Bramlage, who is 82, spoke to Chicoer News about the original construction process of the dam and their thoughts after the crisis. “I saw they should have done repair long before it went out,” Bramlage told the news outlet. “They didn’t want to spend the money. Now they’ve got to spend lots of money.” Originally, the then-20-something builder received $3.28 an hour for his labor. Now, some recent dam repairs have reportedly cost $4.7 million a day.

Returning to the fully-lifted evacuation orders: One million non-human evacuees of the emergency, just a subset of a group of millions more who were rescued from the dirty waters near the damaged spillway, were released on Monday into the Feather River near Yuba City. As The Mercury News reports, these were one million rescued spring-run Chinook salmon and steelhead trout, who were put out into the river by the Department of Fish and Wildlife with hopes that they'd make it downstream and toward the ocean before more coming rains swell the river and make the passage dangerous for them.

Previously: Oroville Dam Will Begin Releasing Water Down Its Heavily Damaged Spillway Again Next Week