BOISE, Idaho -

Executives for Idaho's biggest utility say it's essential to invest $130 million into upgrades at a Wyoming coal-fired power plant.
    
Idaho Power Co. Senior Vice President Lisa Grow told state regulators on Thursday that not investing in the Jim Bridger plant would be a great risk for the company.
    
Grow also said the company would have to think seriously about any decision by the Public Utilities Commission that rejects reliance on ratepayers to bear the costs of the upgrades.
    
The Idaho Statesman reports (http://bit.ly/1gxvbg1 ) the upgrades at the Rock Springs, Wyo., facility are need to comply with regional haze rules under the federal Clean Air Act.
    
Idaho Power owns a third of the plant, while Pacificorp is the majority owner. Utah and Wyoming have already approved requests for the improvements.