Green Spaces Can Save Cities Millions Annually

Blog posted On January 24, 2018

City planners incorporate tree canopies and other green spaces in urban design because of their proven ability to lower wind speed and energy consumption, reduce pollution and heat, and improve neighborhoods’ livability.  A new study from Ecological Modelling estimates planting trees can save cities as much as $505 million annually on costs related to air pollution, storm water drainage, energy, and carbon emissions. 

Researchers from the SUNY College of Environmental Science and Forestry and Parthenope University of Naples examined major metropolitan areas around the world to determine the economic impact of trees in urban spaces.  Based on data from cities including Beijing, Cairo, London, and Los Angeles, trees generate a value of $1.2 million per square kilometer.  This value is only expected to increase, especially in large “megacities” with populations exceeding 10 million, and space to develop more green space. 

Today, tree coverage in megacities ranges anywhere from 8.1% to 36% but has the potential to cover an average of 15.6% to 24%.  As the modern city landscape changes, and unused space emerges, there is more of an opportunity to repurpose this space into planting ground for trees and greenery.  With the growing popularity of rideshare and the development of autonomous vehicles, empty spaces like parking lots have the potential to become tree canopies when they are no longer needed. 

The study shows that the median reduction in air pollution alone, saves cities $482 million annually.  Cities are also saving about $11 million annually in the reduction in the amount of stormwater processed by wastewater plants, $8 million annually in reduction in the amount of carbon emissions, and about $500,000 annually in the reduction in heating and cooling.

Researchers from the Urban Forestry and Urban Greening journal calculated that cities have the potential to collect a $5.82 return for every $1 spent on maintaining trees and urban gardens.  They estimate the state of California’s 9.1 million street trees have a value of $1 billion or $111 per tree. 

The measurable financial incentive combined with the environmental benefits may see the inclusions of more trees and green spaces in evolving city landscapes to come. 

Sources: Fast Company, Fast Company