Flooding at Humboldt Redwoods

Rockefeller flood
Floodwaters in Rockefeller Forest

The Great Flood of 1861-62
The most devastating California flood in recorded history began on the Humboldt coast, eventually flooded the central valleys, and caused devastation and loss of life as far south as San Diego. Often compared to the Biblical flood of Noah’s time, a “Noachian deluge” started in December of 1861 and poured for weeks into January of 1862.

Mild north coast snow and rains were joined by heavy precipitation from an “atmospheric river” (a sub-tropical wet-weather pattern about a mile above sea level, nicknamed a pineapple express). The polar jet stream drove thick waves of warm rain from the Hawaiian Islands to the Pacific Coast. The snowpack melted and inundated waterways.

Statewide flood damage cost an estimated $10 million in 1862 dollars, and more than 200,000 head of cattle lost their lives. The state went bankrupt, and California’s economy evolved from ranching to farm-based.

 

Humboldt Flood 1955
1955 Flood Damage at Humboldt

The “Christmas Flood” of 1955-56
On December 21st and 22nd, 1955, a series of warm rainstorms melted the snowpack, causing Redwood Creek and the Smith, Klamath, Mad, Mattole and Russian rivers to run over. The Bull Creek area flood plain, a heavily logged area with no flood-control plan, was inundated with rising water, the most since the record floods of 1861-62. U.S. Highway 101 lay beneath several feet of the Klamath River. In Humboldt Redwoods State Park, the Eel River rose to record highs.

At Upper Bull Creek in Humboldt Redwoods State Park, hundreds of large trees, some 10-15 feet in diameter, had been undercut by floodwater-powered logjams. The greatest damage occurred in the Richardson, Stephens and Williams Groves. The job of removing tons of debris and sediment notwithstanding, park workers were confident that at least five of the campgrounds in the Redwood Region would be in full operation that season.

By April, rain was still falling. Enormous redwood trees were still collapsing where poor drainage existed. Bull Creek itself was jammed with at least 500 fallen trees. For perhaps the first time in state park history, hired professional loggers worked quickly to remove dead trees from the creek bed. Not long after they were finished, a second flood knocked 20 more trees into Bull Creek.

Extensive reconstruction of stream banks saved the “Giant Tree” and other huge iconic redwoods from destruction. Surviving park buildings from the Bull Creek area were moved to the Burlington campground, but those buildings would all need to be replumbed, rewired, repaired and painted. Roads would have to be rebuilt and resurfaced. A group of honor camp inmates helped salvage and clean up. Trees fell, waters churned, and property damage was profound, but, thankfully, no people were injured in the “Hundred Year Flood” of 1955.

The 1964-65 Megaflood
In December-January of 1964-65, another severe winter flood brought record-breaking wholesale destruction to Humboldt Redwoods State Park. The ferocity of this flood earned it the title of “Thousand-Year Flood.”

The ruthless winter storms that struck California’s north coast beginning on December 21, 1964, are still called the “greatest natural disaster” ever experienced by the Pacific Northwest states. Snow was on the ground, and the hammering rains were warm. The Eel, Smith, Klamath, Trinity, Salmon and Mad rivers were all long past flood stage that day and the next. Northern California’s Humboldt, Del Norte, Mendocino, Siskiyou, Trinity and Sonoma counties experienced record water levels for the 20th century.

When this storm hit, Crescent City was still trying to recover from tsunami damage following the Alaskan earthquake earlier that year. Floodwaters, laden with jammed logs and houses ripped from their foundations, roared across at least 16 highway bridges, destroying them all and leaving residents isolated for months.

 

HumFlood 1965
Founder’s Grove Flood Aftermath

Humboldt Redwoods State Park
As the waters reached the park, they began to gouge out the bed of Bull Creek, tumbling downstream toward the Rockefeller Forest. The seething river knocked over enormous redwoods outright, and undercut those still standing along the creek bed. When the waters receded, the forest floor and the banks of the creek had suffered intense damage, and several feet of silt covered the fine, delicate root systems of the forest’s trees, literally suffocating them.

Department employees inspected the Women’s Federation Club Grove, reporting that the area was covered in a deep layer of sticky silt. At Stephens Grove, the damage was so severe and the mud so deep that crews could not get cleanup equipment close enough to use it. At Williams Grove, the campsites were still under as much as 35 feet of water. These former campgrounds are now day-use areas.

Along Bull Creek, park employees tried to replace the eroded areas with gravel for support. They climbed their way around and over giant, tumbled redwoods that had dammed up the creek and added to the erosion. The park’s salmon spawning grounds had been nearly decimated. Trees that had overhung the places where the salmon hid in the shadows were gone, and landslides continued to pour debris into the creek. Staff was having limited success at stopping the erosion, and in some cases the problem had been made worse by the treatment.

In the hills above the creek, loggers began cutting trees again, underscoring the need for California State Parks to find a way to protect the trees. Before long, staff began to realize that the only way to stop the erosion of Bull Creek and the Rockefeller Forest area was for the division to acquire the Bull Creek watershed. However, local residents did not want to give up their land. Although attempts were made to pay fair market value with funds provided by the Save the Redwoods League and the State of California, State Parks finally acquired the land through eminent domain.

Tree-ring reconstruction in the Central Valley and sedimentary core sampling in the Santa Barbara Basin show cyclical evidence of severe droughts followed by “megafloods” in California about every 200 years. The scientists studying these patterns link flooding to the 208-year Suess Cycle of solar activity; some think that we may expect another lengthy and costly flood in the first half of this century.

For the present, Humboldt Redwoods State Park is peaceful, relaxing and inspiring—as it has always been. However, California’s rivers still tend to overflow their banks in winter, and park staff continue to seek ways to stabilize the hillsides in this vulnerable, vital watershed.