Two of the most destructive fires in state history — the Valley and Butte — are expected to cost insurers $1 billion in claims, the California Department of Insurance reported Monday. A majority of the estimated insurance costs — $700 million — were generated when the Valley fire swept through Lake, Napa and Sonoma counties last year, consuming 76,067 acres, killing four people and damaging or destroying almost 2,000 structures.

Nearly all the damage from the September blaze — the third most destructive in state history — occurred in Lake County.

County Supervisor Rob Brown said he’s “not surprised” by the $700 million figure. He noted that numerous businesses — including two resorts, Hoberg’s and Harbin Hot Springs — were among the fire’s casualties.

The Butte fire, the seventh most destructive in state history, damaged or destroyed 818 structures and killed two people as it raged through 70,868 acres in Amador and Calaveras counties. The Valley and Butte fires ignited within days of each other in early September.

So far, insurance companies have received 5,600 claims and paid out more than $500 million to Valley and Butte fire victims, according to the Department of Insurance.

“The Valley and Butte fires were sober reminders of the dangers residents can face in rural areas of the state,” Insurance Commissioner Dave Jones stated in a press release.

While high, the insurance costs are only part of the fire’s price tag.

The Valley fire is expected to cost many millions more in federal and state aide to fire victims and for repairing and replacing roads, utilities and other infrastructure.

There also are unknown costs for people who were not insured. A survey of fire victims is underway in Lake County to better understand their remaining needs.

Caltrans estimates that clearing and repairing state highways in the fire zone will cost about $12 million. Cost estimates were not available Monday from PG&E and AT&T.

The cost for county roads has not yet been determined, but it likely will be in the millions, Public Works Director Scott De Leon said.

“We have a lot of roads that have been heavily impacted,” he said.

The Federal Emergency Management Agency has so far spent almost $6.7 million on housing and other aid for Valley fire victims, officials said.

Another $10 million or more in federal and state funding has been funneled into Lake County to assist with housing, jobs, future firefighting and lost county revenue.

You can reach Staff Writer Glenda Anderson at 462-6473 or glenda.anderson@pressdemocrat.com.

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