The Puget Sound region has become one of the fastest growing areas in terms of population and development. The expansion of impervious surfaces, often coupled with grading and tree removal, has increased stormwater runoff volumes, which contribute to flooding, erosion, and water pollution. Fortunately, tree canopy in urban areas can reduce stormwater volume and filter water, while also providing wildlife habitat, shade, and improved air quality, human health, and livability. 

What began (in Phase I) as a quest to accurately quantify the value of urban tree canopy for stormwater management in Puget Sound, the “Trees and Stormwater” project evolved to produce valuable resources for jurisdictions that go beyond stormwater. While the Technical Report from the tree canopy/hydrology modeling study demonstrates the effective role trees (especially conifers) play in stormwater management, the companion Handbook expands the conversation to consider an interdisciplinary approach to collaboration and co-design of green infrastructure and urban forest management for the compounding benefits provided to the community.

However, growth planning, management policies, and implementation practices rarely embrace trees as a part of the stormwater solution, let alone see them play a valuable role in community resilience. As this web-based Toolkit was being developed in Phase II to provide resources for more productive collaboration, the power of strong partnerships, influential champions, and public engagement were revealed as critical components for successful integration that can support a robust urban forestry element in a community’s agenda for resilience.