A new study commissioned by an association of river commercial groups says removing the four Lower Snake River dams to improve salmon runs would cost $2.3 billion over the next 30 years, boost state carbon emissions and jeopardize already fragile local and regional economies.

“Dam breaching extremists talk about how easy and inexpensive it would be to compensate Washington, Oregon and Idaho businesses and residents if the lower Snake River dams were removed,” PNWA Executive Director Kristin Meira said Monday.