In this Watershed Plan, we demonstrate an approach for assessing potential co-benefits—the additional services and amenities that are provided beyond the intended benefit—in the Islais Creek Watershed in southeast San Francisco. In this case study, we first identify opportunity areas for green stormwater infrastructure (GSI) that result in stormwater runoff and polychlorinated biphenyl (PCB) reductions. We then use these scenarios to assess the potential for those projects to provide co-benefits of biodiversity, tree canopy access, and urban heat mitigation. Using this approach, we were able to identify hotspots within the Islais Creek Watershed that would most benefit from GSI installations based on the total benefit provided. Urban spaces are crowded and complex, making the planning for multiple benefits important for achieving the often multiple goals of municipalities including resilience, biodiversity support, pollution reduction, and community needs.