MAX Green Line

The MAX Green Line is a light rail service in Portland, Oregon, United States, operated by TriMet as part of the MAX Light Rail system. It is 15 miles (24.1 km) long and serves 30 stations from the PSU South stations to Clackamas Town Center Transit Center; it connects Portland State University (PSU), Portland City Center, Northeast Portland, Southeast Portland, and Clackamas. The Green Line is the only service that shares parts of its route with the four other MAX services, sharing the Portland Transit Mall with the Orange and Yellow lines and the Banfield segment of the Eastside MAX with the Blue and Red lines. Southbound from Gateway/Northeast 99th Avenue Transit Center, it operates the Interstate 205 (I-205) segment through to Clackamas Town Center. Service runs for approximately 211⁄2 hours daily with a headway of 15 minutes during most of the day. It is the third-busiest line in the system, carrying an average of 19,160 riders per day on weekdays in September 2019.

Planning for light rail in Clackamas County began with a proposal in the mid-1980s to build two separate lines, of which one was envisioned from Portland International Airport to Clackamas Town Center using the I-205 busway. Feasibility studies conducted in the early 1990s shifted plans away from I-205 and culminated in the South/North Corridor project, which failed to secure voter-backed funding over several ballot measures. In 2001, regional planners unveiled the South Corridor Transportation Project, a two-phased revision of the South/North project that sought light rail for I-205 and the Portland Transit Mall in its first phase. With the support of local residents, the I-205/Portland Mall Light Rail Project was approved in 2003. Construction began in early 2007 and spanned over two years. The project opened in two phases starting with the Portland Transit Mall in August 2009 and I-205 the following month. Green Line service commenced on September 12, 2009.

TriMet had intended to extend MAX to Southwest Portland, Tigard, and Tualatin with the Southwest Corridor Light Rail Project. The 13-station, 11-mile (18 km) extension would have begun construction in 2022 and opened in 2027 with service from the Green Line. On November 3, 2020, voters declined a tax ballot measure that would have provided local funding, putting the project on hold.