On a Tuesday morning in October, just before noon, the San Francisco port is bustling with life. Shoppers line up for late summer produce and specialty coffee at a farmer’s market in front of the iconic Ferry Building, and suited professionals settle on benches near the water to enjoy their lunches. It’s unlikely that many of these daytime revelers realize that they are just a few feet from the seawall: a critical barricade protecting San Francisco from the looming impacts of climate change, and an accessory in a lawsuit that’s demanding oil companies pay for these impacts. Executive Director of the San Francisco Port Elaine Forbes, who has just switched from high-heels to walking shoes for our stroll, points to the crowd. “There’s 24 million people that come and go, use the seawall, and have no idea that it’s that core infrastructure that makes for this beautiful place.” Forbes leads me around the Ferry Building, walking along the water towards the San Francisco–Oakland Bay Bridge to show me what’s at stake. The six-foot-tall seawall, which sits just below the cement we’re standing on, took nearly four decades to construct and was completed in 1916. But more than a century later, the wall is badly in need of updates. And because of warming oceans, sea levels are expected to increase up to 66 inches between 2000-2100. Strengthening the wall has become the port’s top priority in light of this threat (as well as the potential for a large projected earthquake). The upgrades — which include an estimated $3 billion in sea level rise mitigation and $2 billion in earthquake retrofitting — will come at a huge cost to the city. “Right now, we have zero construction dollars,” Forbes says. To amass the funds, the city and the port are planning ballot initiatives and working with the US Army Corps of Engineers, which might chip in.