30 million juvenile salmon were transferred to the Pacific Ocean after a record drought left the Sacramento River too low for migration. Mark Conlin/Getty Images

California's drought is so severe this year that there is not enough water for salmon to make their annual trip up the Sacramento River to spawn, forcing the state to truck them instead, officials said.

The extraordinary effort, however, will have the side effect that the freshly spawned fish will not know where to go when they are ready to make the trip up the river as adults in three years, experts said.

Steve Martarano of the California Fish & Wildlife Service it will take 22 days to carry out the large scale operation. The Chinook smolts, about 3 inches in length, will be transported in trucks carrying approximately 2,800 gallons of climate-controlled water. Each truck can hold about 130,000 smolts. The young fish will be taken to the Pacific Ocean, he said.

"Because of the environmental conditions this year, water temperatures are not conducive for the fish to have high survival rates this year," Martarano said.

The state teamed up with the Coleman National Fish Hatchery, that has more of the resources needed, and plan to truck out and release the first round, approximately 12 million, of Chinook salmon today.

"Normally we use a fish pump and put the pipe line into the creek and they start their migration there of about 180 miles, giving them a 'cookie crumble route,' and they learn to imprint how to get back when they are adults," said Brett Galyean, deputy project leader at Coleman National Fish Hatchery.

He said trucking was the best option because the fish bypass predators and other creeks they might meander into, meaning there will be more fish out in the ocean, giving commercial value in three years when they're ready to spawn.

Galyean pointed out that there is drawback to trucking. The fish won't have that "cookie crumble" - like bread crumbs marking a trail - and won't know where to track back to when they're adults.

"When they come back up the river, they don't know exactly where to go," Galyean said.

John McManus, executive director of the Golden Gate Salmon Association, is among the California fishing groups who are thrilled about the transport. He said it's important to those in the fishing industry, who depend partly on salmon to make a living, to ensure the baby salmon survive the drought and make their migration to sea.

"As a result of the trucking of salmon today, survival of these fish will be much higher, so fish will come back as adults in 2016," McManus said. "Which increases the chance we'll get a good economic boost for our coastal communities and our inland water waves."

The drought, believed to be the worst in a century, led to Gov. Jerry Brown declaring a state of emergency in January due, asking California residents to use 20 percent less water.

Mark Svoboda is a climatologist with the National Drought Mitigation Center, which monitors the drought weekly at the University of Nebraska Lincoln. He says the problem for fish is a lack of a snow pack, which acts as a bank saving account, holding water which melts gradually over the year. On a normal year, there would be a snow pack there, which melts slowly over months, but the lack of one this year means there is not much water for fish to use.

"There's obviously a connection between what's in the snow pack and how it's released downstream and how that effects fish migration and habitat," Svoboda said. "It's not there now and certainly won't be there later, and that's why they are probably preparing for that now and transporting the fish."