Chico, Calif. -- A life saving effort has come to fruition one year later.
While the Oroville Dam spillway affected thousands, it wasn't just the people who were in danger.
Nearly one million Steelhead eggs became endangered as well.
"We immediately started figuring the steps we needed to take to evacuate the fish and at the same time we're dealing with the eggs inside the hatchery building," said David Lunsford, a Fish and Wildlife Technician.
Silt and debris overwhelmed the hatchery system following the spillway failure.
"We were all scrambling around trying to save the Steelhead and the Chinook that we had here at that time," said Lunsford.
With less than 72 hours to complete fixes on aeration and filtration systems, the engineers went to work.
"We got the turbidity down, which is all the silt," said Lunsford.
The engineers then needed to find a way to purify the city water so they installed charcoal filters.
"We ran into the chlorine issue, it's very bad for fish," said Lunsford.
"This is the beginning of the fish release process, what's going on is we're taking the fish down to where they can be sucked up by these giant vacuums," Harry Morse, Public Information Officer of the California Department Fish and Wildlife.
Throughout the next few days, hatchery trucks will be transporting and releasing the rescued fish on the Feather River, just near Yuba City.
"A year ago at this time, we didn't know if any of the fish would survive, if the eggs would make it through. And it all came to fruition," said Morse.