Portland’s journey toward sustainability began earnestly in the late 20th century when the city made substantial moves against proposed road expansions that would have escalated urban sprawl. This included the transformation of Harbor Drive, a freeway that once ran along the Willamette River, into what is now Tom McCall Waterfront Park—a lush, riverfront park that prioritizes pedestrian and bicycle paths over car traffic. Moreover, Portland was the first U.S. city to enact a comprehensive carbon reduction strategy in 1993, setting a precedent for urban climate action.

The city’s urban growth boundary, established to control sprawl and protect the surrounding farmland, and its robust public transportation system further illustrate its commitment to sustainable urban planning. Additionally, Portland has been a leader in promoting green building practices, with numerous LEED-certified developments dotting its skyline.

However, despite these advancements, Portland faces ongoing challenges. Traffic congestion remains a significant issue, particularly along key arteries like Interstate 5, where expansion projects have sparked debate over their environmental impact. The tension between growth and sustainability continues to shape Portland’s policies and priorities.