Exploring San Francisco's Hidden Tunnels | Bay Curious

With nearly a million residents, San Francisco is bustling with life, but what goes on underneath the city is just as intricate. Built more than a century ago during the gold rush, San Francisco’s sewer system is a feat of engineering that very few get to see. Bay Curious follows San Francisco Public Utilities Commission Assistant Engineer Megan Abadie on an exploration of the hidden tunnels beneath the city's streets. UPDATE: We removed a quote that included an inaccurate statement about sewer networks across California. Almost all of San Francisco uses a combined sewer system. San Francisco, along with a small part of Sacramento, are the only cities in California that use a combined system.