Urban stormwater is a major contributor to surface water degradation in the United States, prompting cities to invest in green infrastructure - methods that naturally capture, store, and slowly release runoff, such as urban trees.

While green stormwater infrastructure increases in popularity, we are still learning about the role of trees in these innovative practices.

The water quality benefits of forests are widely accepted, yet very few studies have successfully quantified the runoff and pollutant-reducing impacts of trees in the urban landscape.

The Center for Watershed Protection reviewed a total of 159 publications to evaluate the research questions defined in the scope of this project:

1. What is the effectiveness of urban tree planting on reducing runoff, nutrient and sediment?

In spite of the proven value of trees for reducing stormwater flows and pollutants, there remains a widespread lack of understanding, acceptance, and credibility of their use for managing stormwater.