A Washington Department of Ecology report on minimizing damage from massive floods in the Chehalis River Basin considers two main options — build a dam or move farms to higher ground.

The study, which is being circulated for public comment, stems from major floods in 2007 and 2009. High water closed businesses and Interstate 5 at Chehalis and damaged farms, particularly in Lewis County.

Since then, local and state officials have searched for ways to reduce flooding while also enhancing fish runs.

A panel appointed by the governor recommended in 2014 building a dam on the Chehalis River. The Quinault Indian Nation proposed letting the river spread out.

Ecology studied both options, along with ideas such as constructing walls along I-5, and raising levees and buildings.

Ecology’s report estimates the dam and associated projects would cost $601 million to $1.2 billion.

The alternative that includes buying and relocating farms that now occupy as many as 12,100 acres would cost $1.4 billion to $1.7 billion.

To keep farming in the area, growers would have to move to steep and forested land with unsuitable soil, Lewis County farmer Dave Fenn said.

“Basically, it’s totally impractical,” he said.

Ecology’s program manager, Chrissy Bailey, said the agency undertook the study at the request of the governor’s work group. Ecology hasn’t decided whether it will make its own recommendation, she said.

“We understand people’s concerns and reaction,” Bailey said. “This is not something that would happen without landowner willingness on a broad scale.”

Lewis County farmers produced $132 million worth of crops and livestock, according to the U.S. Department of Agriculture’s 2012 census. Fenn said a shrinking farm economy could affect growers who stay.

“What happens if half the people are willing to sell and half aren’t? What happens to the half who aren’t?” he asked. “The impact to (farm) suppliers might be severe.”

Ron Averill, the legislative chairman of the Lewis County Farm Bureau, said it was good that Ecology held the proposal up for scrutiny.

“What farmer is going to move to where he would have the wrong soil and no water rights?” Averill asked. “Needless to say, the Farm Bureau is not happy about the alternative.”

In a letter last year to Ecology, the Quinault tribe said spreading the river over a larger area would enhance fish and wildlife habitat, improve water quality and reduce the severity of floods. It also would eliminate the costs of maintaining a dam, according to the tribe.

The dam would disrupt fish runs, but habitat projects could more than offset the damage, according to Ecology.

Letting the river spread out would benefit fish more than any other option, the report states.

That alternative, however, would not provide the needed flood relief, said Jay Gordon, policy director for the Washington State Dairy Federation and a member of the governor’s work group.

“It doesn’t appear to meet the goals we set out,” said Gordon, a dairy farmer in the basin. “It has to be both — fish enhancement and flood control.”

The work group plans to review Ecology’s report and update its recommendation to Gov. Jay Inslee by the end of November. Currently, there is no plan on how to fund any option.