Why cities should be paying attention to their 'green infrastructure'

Thu, 2018-03-22 15:11 -- Doug Peeples

Numerous studies about urban trees have come to the same conclusion: most cities and communities are losing urban tree canopy, that layer of leaves, stems and branches that cover the ground when seen from above. The U.S. Forest Service says the causes are primarily diseases and insects, natural disasters and development. The study described in the story below focuses on a limited range of benefits, but it's also encouraging in a way because it's an indicator that more cities are thinking of their trees more as useful  "green infrastructure" and less as cost centers. With urban populations growing, city leaders and planners envisioning smart city transformations should be considering how much tree canopies can contribute to their livability and sustainability. — Doug Peeples

The growing city of Auburn, Alabama is among 11 cities participating in a study that is expected to yield recommendations for how those cities can improve the way they manage their trees to mitigate problems caused by storm water, flooding and polluted water runoff.

The Green Infrastructure Center, a non-profit based in Charlottesville, VA, will conduct the Forest Service-supported study across six states. Quoted in an article in the Opelika-Auburn News, Green Infrastructure Center Executive Director Karen Firehock said the study would also cover additional ground. "The study will also help create healthier communities by realizing the many benefits that trees provide other than just clean air and shade."

The cities chosen for the study, she said, were selected based on their willingness to try new approaches.

Daniel Ballard, also quoted in the article, is Auburn's watershed division manager. For Ballard, "Trees are the original green infrastructure." As he pointed out, Auburn is a good choice for the study because the city is expanding quickly and growing cities typically remove at least some of their trees to make way for development to accommodate the growing population. He thinks the study will help the city find better ways to manage its trees, specifically to improve water quality. It's a major issue for him because water quality in the city's watersheds have been a concern.

Urban trees have demonstrated that they provide other valuable benefits for cities. And as an Australian urban tree canopy study noted, those benefits can be worth millions of dollars. They include increased property values resulting from additional tree plantings, reduced summer peak temperatures and reduced building temperatures, not to mention the aesthetic benefits.

For Auburn, the study comes at a good time because the city has been working on a green infrastructure master plan that will cover parks, green spaces, bike paths, walkways and other assets. "This project filled a gap in that master planning process," Ballard said. "Although we're not evaluating urban tree canopy in our green infrastructure master plan, we are in that process looking holistically at the way we manage storm water and not just trees."

Doug Peeples is a Portland, Oregon-based writer specializing in technology and energy. Follow @smartccouncil on Twitter.