Giving Green Streets the Green Light

June 2019

(Washington, D.C.): The vast majority of assessed water bodies across the United States are designated as impaired. Cities contribute to the problem with stormwater runoff from roads, buildings, sidewalks, and other impervious surfaces polluting our rivers, lakes, and streams. A new report from the Environmental Law Institute (ELI) identifies 14 forward-thinking local governments that are taking on this problem through Green Streets policies and offers 13 key recommendations for municipalities to craft their own robust and effective Green Streets policy.

“A growing number of cities are pursuing Green Streets, which directly mitigate the environmental impact of roadways by incorporating green infrastructure into capital projects in the public right-of-way,” said lead report author Cynthia Harris, Deputy Director of ELI’s Center for State, Tribal, and Local Environmental Programs. “Considering that one-quarter of U.S. urban areas are covered by roads, buildings, sidewalks, and other impervious surfaces, policies that systematically integrate green infrastructure over time can have a real and positive impact on our waterways.”

“Green infrastructure” practices mimic natural systems to reduce flooding, control erosion, and prevent polluted runoff from entering streams and other water bodies. Several local governments are building Green Streets, which incorporate these systems into the public right-of-way. But a growing number of forward-thinking localities are going further, implementing Green Streets policies, which mandate integrating green infrastructure every time a municipality undertakes a capital project or significant maintenance work in the existing public right-of-way.

The report, Giving Green Streets the Green Light: Improving Water Quality Through Capital Improvement Policies, offers best practices for local governments considering adopting policies to incorporate green infrastructure into all public right-of-way construction/reconstruction projects, where feasible. The report largely focuses on the Chesapeake Bay Watershed, yet the findings are applicable nationwide.

“Implemented correctly, Green Streets can reduce and mitigate stormwater and other environmental impacts of surface transportation, which can provide ancillary environmental, economic, and social benefits,” Harris added.

ELI synthesized the results of its research and analysis into a Model Ordinance that is customizable—taking into consideration different local priorities and capacities—and that local governments across the United States can use as a starting point for developing their own Green Streets policy.

Before ELI could begin, it had to define what it means to have a Green Streets policy. ELI concluded that Green Streets polices should: (1) be formally adopted by a local government and connected with its capital improvement program; (2) include a trigger for integrating green infrastructure elements into both new and preexisting roads and streets; (3) integrate green infrastructure explicitly for the purpose of improving stormwater management and water pollution mitigation; and (4) be systematic in nature rather than piecemeal. ELI ultimately identified 14 jurisdictions of representative localities currently implementing Green Streets policies that meet this stringent definition.

ELI then surveyed all 14 Green Streets jurisdictions and prepared case studies based on information gathered from the surveys, telephone interviews, and independent research. ELI’s analysis produced a set of 13 recommendations for crafting a robust and effective Green Streets policy. The report discusses each recommendation in detail, notes how each Green Streets jurisdiction performs in applying that recommendation, and provides specific examples.

The full report and executive summary are available at:

Cynthia Harris is available for interview.

This report was funded by the Chesapeake Bay Trust under grant number 15987. This project has been funded wholly or in part by the United States Environmental Protection Agency under assistance agreement CB96336601 to Maryland Department of Natural Resources. The contents of this document do not necessarily reflect the views and policies of the Environmental Protection Agency, nor does EPA endorse trade names or recommend the use of commercial products mentioned in this document. Program partners include United States Environmental Protection Agency Region 3, Chesapeake Bay Program, Maryland Department of Natural Resources, Baltimore City’s Office of Sustainability, and the Chesapeake Bay Trust.