San Francisco Great Highway Closure Reroutes Thousands of Commuters, Sparking Concerns for School Traffic

San Francisco’s Upper Great Highway has permanently transitioned to a car-free public park, a move that has significantly altered traffic patterns in surrounding neighborhoods and drawn criticism from some community groups. The conversion of the two-mile stretch between Lincoln Way and Sloat Boulevard, approved by voters via Proposition K and subsequently by the California Coastal Commission in late 2024, aims to create an oceanfront park. However, the change has led to notable traffic diversions, particularly impacting local commutes.

Concerns about the closure's immediate effects on daily life have been vocalized. According to a recent social media post by the account "@StopAAPIHate," the closure of the Great Highway has caused "15,000 cars and 20,000 commuters [to] flood through the neighborhoods." The tweet further asserted that this diversion is "impacting @SFUnified students and family commute," calling on city officials to intervene.

Data from the San Francisco Municipal Transportation Agency (SFMTA) indicates a clear shift in traffic. As of July 2025, Chain of Lakes Drive, a key alternative route, has seen approximately 2,000 more vehicles per day compared to pre-closure levels, while the Lower Great Highway experienced an increase of about 700 vehicles daily. A 2021 study by the San Francisco County Transportation Authority (SFCTA) had previously anticipated such shifts, predicting that while traffic on the Upper Great Highway would decrease by up to 25%, routes like Chain of Lakes would see increased congestion.

The SFCTA study also projected that 60-70% of the diverted traffic would reroute to Sunset Boulevard, with 20-25% using local neighborhood streets and 5-10% opting for 19th Avenue. While some reports suggest Sunset Boulevard can largely accommodate the increased volume with minimal slowdowns, residents in the Outer Sunset and Richmond districts, which were largely opposed to Proposition K, continue to report extended commute times and increased congestion on residential roads.

City officials and proponents of the park conversion acknowledge the traffic challenges and have initiated mitigation efforts. Supervisor Joel Engardio, a key supporter of Proposition K, has secured funding for traffic improvements, including new signals at critical intersections like Lincoln Way near Chain of Lakes Drive East, with construction expected to begin in fall 2025. Despite these measures, the debate over the long-term traffic impact and the future of the Great Highway remains a contentious issue within the community.