Columbia River Gorge vegetation management project. Preliminary environmental assessment

摘要

The Bonneville Power Administration (BPA) operates the Federal Columbia River Transmission System, which supplies power to the Pacific Northwest (PNW) and nearby states. BPA must maintain the system's electrical reliability. Trees and other tall-growing vegetation threaten that reliability by potentially growing or falling into transmission lines. Shrubs and similar vegetation may also threaten system reliability by growing into access roads and keeping maintenance crews from needed access to transmission towers and lines. BPA needs to be able to keep its rights-of-way sufficiently clear to ensure maintenance and operational reliability. More than 368 kilometers (km) (230 miles (mi.)) of BPA transmission lines are operated in the Columbia River Gorge National Scenic Area (NSA), which lies mainly on the border between the states of oregon and Washington. Much of that area is forested. Reliability of two BPA transmission line corridors is threatened in the NSA by vegetation growth. BPA needs to find an effective and cost-efficient way to prevent tall-growing vegetation from disrupting system operations, and to keep access roads clear, while still protecting the environment and complying with national policies and mandates.