Environmental advocates and tribes are raising concerns about a proposed electric transmission line under the Columbia River from the east end of the Gorge to Portland, Oregon. The nearly $2 billion Cascade Renewable Transmission System would move 1,100 megawatts of power from The Dalles to a substation in the Northwest Portland neighborhood of Harborton. The Connecticut-based PowerBridge has proposed using a hydroplow to dig a 2-foot-wide trench using water jets along roughly 80 miles of riverbed, then burying a 12-inch cable bundle 10 to 15 feet below the river. Environmental advocates argue the project poses serious risks to water quality, endangered fish, tribal treaty rights and cultural resources. The project has pending permit applications with Oregon, Washington and the U.S. Army Corps of Engineers and will undergo environmental review and public comment periods before construction can begin.