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Shift Happens

Cities turn a new leaf to count the ROI of trees

The natural capital provided by an urban canopy provides measurable material benefits.

Last year we wrote about "Urban materiality and a new network of sustainable cities." It touched on the growing activity by cities to measure, manage and report on their sustainability performance. 

Assessing what topics are material is fast becoming a best practice among companies and cities alike. Both are looking across their value chain, beyond their own operations, to better understand how they affect their suppliers, employees and the communities where they operate. Companies better understand that by being a good corporate citizen in their local communities, they are also serving their employees and their families.

Cities and companies have found a common denominator — people, otherwise known as human capital. A number of studies show that a happy and healthy community — one that is environmentally, socially and economically balanced — has measurable and positive impacts on a region and the quality of life. One way this is coming to fruition is through trees. 

As U.S. Forest Service Chief Tom Tidwell said, "Urban trees are the hardest working trees in America."

Why trees? They have impact 

The world’s most widely used approach to reporting on sustainability performance is the 20-year old Global Reporting Initiative. GRI asks reporters to engage stakeholders to determine its most important (material) issues and where they occur.

As cities and other public agencies conduct materiality assessments, they consistently identify material issues that relate to the overall health and well-being of their people. This seems rather intuitive, but how does one prove it or measure it?

The value of aesthetics, beauty and nature

Atlanta, Georgia

In 2015, Atlanta applied applied the GRI G4 Guidelines and consulted with over 300 local citizens for input on the most material issues for the city. They looked at the performance of factors economic (growing business and sustainability planning), environmental (energy, recycling, land use, air quality, mobility) as well as social and community-related (sustainable education, community health).

Atlanta goes even deeper into biodiversity and land use, and specifically discusses and quantifies a range of metrics relating to acres of parks, access to them, trees planted and community engagement and involvement. In fact, the Forest Service classifies Atlanta as one of the most forested urban areas in the country.

Pittsburgh, Pennsylvania

Pittsburgh takes its regional sustainability issues very seriously, as our column described last year. Sustainable Pittsburgh has been collaborating with a range of regional organizations over the last 18 years in an effort to raise awareness and engage regional stakeholders. The regional organization considers natural spaces, forests and the urban canopy integral assets to Pittsburgh’s overall quality of life and thus economic development.

"Few investments naturally deliver on so many co-benefits as maintaining urban trees," said Court Gould, executive director of Sustainable Pittsburgh. "Our actuarial friends have a field day quantifying the natural capital trees provide silently day in and out.

The value of urban tree cover can readily be monetized in returns on CO2 sequestration, heat island mitigation, reducing rainwater runoff, improving air and water quality.

"While a seemingly crude gesture in the face of the natural grandeur, the value of urban tree cover readily can be monetized in returns on CO2 sequestration, heat island mitigation, reducing rainwater runoff, improving air and water quality, not to mention all the remarkable effects trees have on reducing crime, improving human health and raising property values. A plant-it-first urban strategy is the smart money to grow on."

Tree Pittsburgh led the creation of the city’s first Urban Forest Master Plan in 2011. The planning model was driven by four questions: What do we have? What do we want? How do we get there? How are we doing?

Executive Director Danielle Crumrine is leading the effort to enhance Pittsburgh's vitality by restoring and protecting the urban forest through community maintenance, planting, education and advocacy. 

"We are engaging leaders to slow and reverse the decline in the number of trees in our neighborhoods due to a variety of causes, including construction, pollution, disease and neglect," she said. "We center much of our resources around communities where tree canopy is below average, and we can calculate how many trees we need to plan and preserve in order to grow the canopy."

Tree Pittsburgh is reassessing the status and annual benefits of its Urban Tree Canopy. The 2011 Master Plan documented the total annual benefit of the urban forest at over $7 million, and  structural value of the complete urban forest over $1 billion.

Despite its best effort, Tree Pittsburgh said the Emerald Ash Borer, coupled with development, have drastically offset advancements. Advocacy will be key to achieving a more robust urban forest. The new data will be used to make the case for stricter zoning regulations and tree protection ordinances.

Quantifying and valuing the impacts of the canopy

In the late 1800s and early 1900s, Cleveland was nicknamed the "Forest City." Because of growth and development, Cleveland since has lost almost half its canopy, about 100,000 trees. The loss is much more than aesthetic. The city loses tens of millions of dollars of value each year associated with stormwater control, air pollution, energy costs and property values. Loss of trees also public health, including asthma rates and mental health. 

An immense body of global work provides tangible, quantifiable and monetized information about the positive impact of trees.

Even the current canopy provides Clevelanders with over $28 million in ecosystem services every year. This figure is derived using U.S. Forest Service’s i-Tree modeling and EPA’s Environmental Benefits Mapping and Analysis Program (BenMAP), as outlined in The Cleveland Tree Plan (PDF).

Last year Cleveland formally launched its Tree Plan, which was approved by the Planning Commission in the spring. The Tree Coalition (PDF) was established to implement this plan, which includes nine actions around three main goals:

  1. Recognize trees as critical community infrastructure. 
  2. Reverse the trend of canopy loss, and do so equitably across all neighborhoods.
  3. Assume full stewardship for tree infrastructure, including maintenance.

This is just one of numerous examples of what cities, mayors, city planners and city councils can do to have a quantifiable impact on the health and well-being of their communities. 

As President Franklin Roosevelt said, "A nation that destroys its soils destroys itself. Forests are the lungs of our land, purifying the air and giving fresh strength to our people."

Global leadership examples

An immense body of global work provides tangible, quantifiable and monetized information about the positive impact of trees. If you’re a mayor, a city or county council member, a city planner or just an interested citizen, here are just some of the amazing (financially environmentally and socially quantifiable) impacts of tree programs from around the world.

2015 — Cleveland, Ohio: Cleveland’s canopy was estimated, even at its lowest level, to provide Clevelanders with over $28 million in ecosystem services per year.

2015 — London, England: London’s 8.4 million urban trees return $172.7 million (PDF) in benefits annually.

2014 — Austin, Texas: Austin’s forests are estimated (PDF) to reduce annual residential energy costs by $18.9 million per year.

2014 — Australia: Where Are All The Trees (PDF)? This report provides a starting point for councils, developers and decision makers to better understand benefits of the existing tree canopy in their local areas and guidance on how to measure it.

2013 — Toronto, Canada: Toronto’s urban tree canopy (PDF) is a vital city asset with an estimated structural value of $7.1 billion.

What’s a city to do?

Cities, their mayors, councils and planning commissions are rapidly embracing the concepts of sustainability and implementing a range of valuable programs. Regardless, there needs to be a strong business case for the investments made and a documented return on investment.

The examples above are globally recognized methods for measuring, managing and reporting on the impacts of urban sustainability efforts. Local governments can leverage this scientific work and the precedents set around the world to not only make the case for sustainability, but to make the connection to economic vitality and community well-being. 

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