With determination and ingenuity, staff and volunteers find ways to save the fish
On Feb. 7, the day officials first noticed damage to the Oroville Dam spillway, Anna Kastner got a phone call from the Department of Water Resources. As manager of the Feather River Fish Hatchery, she was asked to have a plan in place to release all of the fish into the river. Release them? she thought. No way.
Kastner decided to come up with a way to move them instead. She called over to the Thermalito annex hatchery facility on Highway 99 and learned it was empty. So, the next day, hatchery employees prepared it for incoming fish. Within 48 hours of being asked to prepare to release the fish from the hatchery, 5 million of them were loaded into trucks—mobilized from throughout the North State—and transferred to Thermalito. Because of their small size, the last million had to be loaded by hand, rather than by pump.
Sometime during the evening of Feb. 7, Kastner said, the water flowing down the Feather River, through the spillway that was eroding, became the consistency of soft-serve ice cream. That promised to clog screens and hoses, not to mention choke the fish. And in fact, it did do damage to the hatchery facility. But, determined not to release the fish except as a last resort, dozens of staff and volunteers pulled together to find a way to save them—and the many eggs that could not be moved off-site.
“Releasing them at this stage,” Kastner said, “probably 80 percent of them would not have survived. The very, very tiny ones wouldn’t have been able to make it with the current and the mud in the water. This way, we could at least give them a chance.”
The chinook salmon at the hatchery are set to be released mid-March. That’s when they’ll start their journey to the ocean before returning to the Feather River in four to five years to spawn. And while the hatchery ensures that a majority of those that return will indeed spawn, the number of fish that actually make it that far is already minimal. So the larger and healthier they are at the outset of their journey, the better chance they have of finding their way back to the hatchery.
The Feather River Fish Hatchery was built to mitigate the loss of critical habitat due to the Oroville Dam. In addition to chinook salmon, it’s also home to steelhead trout, which, unlike the chinook, can spawn multiple times throughout their lives. This time of year, most of them are still in egg form. These eggs—over a million of them—sit on trays inside the hatchery building. Water is run through the trays, which are stacked on industrial shelves. Because of their fragile state, the eggs could not be moved with the more mature salmon.
During a visit to the hatchery last week, while walking from the large aeration tank that’s fed from the Feather River diversion pool, Clint Garman, environmental scientist for the state Department of Fish and Wildlife, explained how the hatchery managed to save the eggs. A fire hose attached to a hydrant on-site pumped—and was still pumping last week—water into a charcoal filtration system to filter out the chlorine. (Chlorine, which is not present in river water, will kill the fish.) From there, several garden hoses were hooked in to keep water flowing through the egg trays. To make matters more complicated, the hydrant water had to be mixed with some river water in order to keep the temperature down.
“At one point, they had workers here cleaning each tray about once an hour to get rid of all the silt,” Garman said. The aeration tank, which pumps oxygen into the water to speed up the fishes’ growth, suffered broken screens and other damage due to mud in the water, he said. They’ll wait until after the spring run is released to open it up and fully assess the situation, however.
Over in the concrete holding tanks, which usually are home to the salmon as they grow, debris was already mostly cleaned up. Garman explained that the few tanks that did still hold fish—the Thermalito annex is not big enough to hold them all, and the ones left behind were too small to be pumped into the trucks—were rigged as well to filter out as much of the gunk as possible so as not to kill the fish.
“Typically you can see to the bottom of the pond,” he said. Even that day, while far from soft-serve, it was difficult to pinpoint fish amid the murk.
Both Garman and Kastner agreed the hatchery isn’t out of the woods yet. With plans to repair the spillway, Garman said, they’re not sure if another mud- and debris-filled flow of water is in their future. So, for now, the hydrant is still in use for the steelhead. And the salmon that were moved will remain where they are.
“This fish cannot be replaced,” Kastner said. “You cannot get more salmon. Once they’re removed, we’ll never get them back.”