The Chinatown neighborhood of San Francisco is home to 10,000 residents and has long been one of the most densely populated neighborhoods in the country not served by an underground transit system until the opening of the SFMTA Central Subway extension project in early 2023. Stockton Street serves both as a bustling commercial and retail center, and a thoroughfare for the city’s bus lines and suffered from heavy congestion. The Central Subway extension provides residents and visitors to Chinatown with a reliable and convenient public transportation alternative and links this vibrant neighborhood to the rest of the city.

Due to the existing BART and Muni underground crossings at Market Street and the slope on Stockton Street up towards Washington Street, the tracks at the Chinatown Station are over 100-ft below the sidewalk elevation. This creates one of the deepest excavations in San Francisco in a tight urban setting and presents challenges in terms of architectural layout and construction sequencing. Located at the heart of the Stockton Street retail corridor, the available area for construction staging was extremely limited.

One of the major architectural visions was to bring light into the deep station to improve the spatial experience of the transit users. This was achieved by placement of escalators and permanent cross-lot struts. With a small lot, we designed the permanent retaining walls to also serve as the temporary soil retention system to maximize usable plan area.