More than 14,000 personnel from California and elsewhere in the country are fighting wildfires across the state. The Mendocino Complex Fire is comprised of two neighboring fires that have scorched through thousands of acres each day and destroyed 75 homes. The River Fire has burned 48,663 acres (19,693 hectares) and is 58 percent contained.
As of Monday, the Carr Fire had consumed 163,207 acres and was 45 percent contained.
Some 3,908 firefighters, 441 fire engines, and 15 aircraft continue to battle the flames.
Meanwhile, new evacuations were ordered Saturday near twin fires burning in Mendocino and Lake counties.
The disaster declaration that Trump approved for California on Sunday makes available federal funding to state, local and tribal governments "on a cost-sharing basis for emergency work and the fix or replacement of facilities damaged by the wildfires and high winds in Shasta County".
He tweeted on Monday that the wildfires were being "magnified & made so much worse" because of a Californian policy to divert water into the Pacific Ocean.
McLean said firefighters are using the direct approach to prevent the fires from reaching urban areas along Clear Lake while retreating in national forests "and letting the fire come to us".
"I was stunned when I read this this morning", Henri Grissino-Mayer, a climatologist and biogeographer at the University of Tennessee, told CNN in an email. "Ridiculous. It's true that water is diverted to the coastal cities for a constant water supply but all such water is used by the coastal communities".
Two fires mercilessly roaring through northern California have grown so rapidly that they are now the largest ever to ravage the state, authorities said.
"Battling these relentless fires requires a Herculean effort", California Gov.
Trump issued an Emergency Declaration for the state on July 28, and Brown has now requested that the president declare a major disaster.
NOAH BERGER via Getty Images The Ranch Fire, part of the Mendocino Complex Fire, crests a ridge as Battalion Chief Matt Sully directs firefighting operations on High Valley Rd. near Clearlake Oaks, California, on Sunday.
As a Reason Foundation study noted, the U.S. Forest Service, which is tasked with managing public wildland, once had success in minimizing widespread fires in the early 20th century.
Farther north, crews gained ground against a deadly blaze that has destroyed more than 1,000 homes in and around Redding.
A man watches the Thomas Fire in the hills above Carpinteria, California, December 11, 2017.