A Washington congresswoman and nine state lawmakers have asked Gov. Jay Inslee to help keep Oregon from slapping tolls on bridges Washingtonians use to drive to work in the Portland area.

Congresswoman Jaime Herrera Beutler, a Republican representing southwest Washington, and area state legislators told Inslee in a letter that there is "increasing concern" a tolling "scheme" will make Washingtonians pick up the tab for Oregon infrastructure projects.

"We write to seek your cooperation and active involvement in protecting Washington residents against any Oregon-devised tolling plan that will unfairly charge them to pay for infrastructure that primarily benefits Oregonians," they said to Inslee, a second-term Democrat.

Officials in Oregon, however, have argued tolls are necessary to pay for infrastructure maintenance and to cut down on traffic. They argue only the drivers who use Oregon's roads would have to pay the tolls.

Gov. Jay Inslee, D-Wash.

For his part, Inslee hasn't spoken publicly about Oregon's plan to put tolls on Portland-area highways. A spokeswoman for Inslee said Tuesday that staff in his office are "reviewing the letter and the situation."

Staff in Gov. Kate Brown's office didn't return a request for comment.

The transportation bill Oregon lawmakers passed this year instructs officials to ask the federal government for permission for the tolls by the end of 2018. Toll prices would likely change based on road usage during rush hour, similar to a set of Seattle-area tolls that went online last year.

But assumptions that tolls would be put on Columbia River bridges are premature, said Travis Brouwer, assistant director of the Oregon Department of Transportation.

"I think that [Herrera Beutler] thinks we're further along in knowing what will actually be tolled and how than we are," Brouwer said. "I'm not sure by any means that the most likely place for tolling is at the Columbia River."

U.S. Rep. Jaime Herrera Beutler, R-Wash.

Herrera Beutler has said toll revenue will pay for projects south of Portland, on freeways many Washingtonians don't use. Brouwer said that's not necessarily true.

Depending on the type of toll put in place, he said, there may only be enough money to break even on the tolling system itself -- with nothing left for infrastructure projects. In that case, the point of the toll would be to reduce traffic, not build new lanes, Brouwer said.

Everything is still up in the air. The $5.3 billion transportation bill has been signed by Brown, but doesn't take effect until next month. And officials have barely begun the process of exploring how, where and when tolls could be put on Oregon highways.

Transportation officials have kept their counterparts in Washington up-to-speed about tolling plans, Brouwer said. Staff from Washington's transportation agency and lawmakers from the Vancouver area will also have seats on the advisory board informing Oregon's tolling plan, Brouwer said.

Nevertheless, Herrera Beutler has continued an all-out effort to halt any tolling program near her district. Last week, she successfully pushed an amendment that would keep the U.S. Department of Transportation from inking a tolling agreement with Oregon. The bill containing that amendment has yet to pass the full House.

-- Gordon R. Friedman

503-221-8209; @GordonRFriedman