Can you safely swim in the Hudson River? How about Brooklyn’s Gowanus Canal, one of the most polluted waterways in the nation? Although hard to imagine, New York City’s waters were once not only swimmable but teeming with aquatic life. Water pollution has taken its toll on the urban environment, yet some of the city's aquatic ecosystems are surprisingly rich. In this project‐based capstone, students research and develop plans‐of‐action for solving the water pollution problem in the Gowanus Canal—while simultaneously addressing issues of green open space, sustainable development, and civic engagement.