PORTLAND — The Bonneville Power Administration has picked a Roseburg supplier to provide the cable for a high-voltage transmission line that will run between the utility’s McNary and John Day substations.

BPA signed an agreement with Alcan Cable to buy $9.5 million worth of cable for the new 500-kilovolt power line that will deliver 870 megawatts of energy, mostly from wind.

Construction on the line begins this summer, and BPA expects it to be finished in 2012. Congressman Peter DeFazio praised the project Wednesday, saying it will put people back to work and improve access to wind power.