A satellite view of Baltimore, Maryland, would show plenty of abandoned buildings and parking lots, with parks—such as Patterson and Gwynns Falls parks—scattered throughout. However, while there is an abundance of concrete and asphalt within the city limits, Baltimore is not a city in isolation. Like Washington, D.C. and other nearby urban areas, Baltimore lies within the Chesapeake Bay watershed.
This means Baltimore residents get their drinking water from rivers running into the Bay. The sewage system is also part of the rivers, streams and other tributaries in the area—a connection that sometimes leads to sewage runoff after excessive rainfall. But as Guy Hager, senior director of Great Parks, Clean Streams and Green Communities for the Parks and People Foundation, explained in a recent Baltimore Ecosystem Study field trip, sponsored by the Ecological Society of America, the location of Baltimore is an opportunity to make all residents a little bit healthier.
By removing asphalt, increasing the number of trees and adding green spaces, such as parks and gardens, the non-profit is changing the way Baltimore citizens live in and view the city. “Our objective is to make the city healthier to live in regardless of economic status,” Hager said. “You shouldn’t have to live in a polluted environment…We’re trying to get people to think of the city, not with several parks, but if we connect them all, as living in a park.”
The value of parks is somewhat hard to define—residents near a park probably think it looks nice, but they are unaware of the many services these green spaces actually provide. A specific example in Baltimore was given by Beth Strommen, manager for the Baltimore Office of Sustainability: In recent years, Baltimore could have put $300 million into upgrading the sewage infrastructure to stabilize overflow due to excessive precipitation. This project would have involved heavy construction and many underground, unseen renovations. Instead, said Strommen, the city put that money toward greening neighborhoods—a solution that both enhanced the neighborhoods aesthetically and used vegetation to prevent sewage overflow, and improve drinking water.
These green spaces are also being added north of Baltimore in Philadelphia, which get its drinking water from the Delaware River watershed. For example, a Philadelphia Inquirer article published today described “Clark Park, nine acres of rare urban green space in what was, at the time, a University City neighborhood transitioning from a high-crime reputation.” The park inspired two residents to open a coffee shop across the street, sparking community revitalization. Stories such as these, as encouraging as they are, are scattered; actual statistics of economic opportunities and public health improvement due to green spaces have more of an overall impact.
Just yesterday, the Delaware Valley Regional Planning Commission and the Green Space Alliance presented a comprehensive list of the direct economic values associated with open green spaces, such as those being added in Baltimore and Philadelphia, and the relationship with the watershed. The corresponding report suggested that open spaces enhance home values, protect property, filter drinking water, clean the air and create jobs and listed specific statistics for southeastern Pennsylvania.
Open space adds $16.3 billion to the value of southeastern Pennsylvania’s housing stock. Protected open space generates $240 million annually in property tax revenues to support county and municipal governments and local school districts. Southeastern Pennsylvania realizes nearly $61 million in annual cost savings from protected open spaces’ ability to naturally filter out pollutants and replenish water supply. The total annual benefit generated by natural flood mitigation services is more than $37 million. Trees on protected open space are estimated to provide $17 million in annual air pollution removal and carbon sequestration services.
In addition to the economic value of these spaces, studies have shown the direct relationship between public health and spending time in parks and nature. A New Scientist article published last week outlined several studies supporting the benefits of nature on human health. One study from the American Journal of Preventive Medicine showed an association between high levels of neighborhood greenness and lower odds of children increasing their body mass index in a two year span.
Another study from the Journal of Environmental Psychology, and reported by Nora Schultz in the article, indicated that people exposed to natural settings recovered from stressful events more quickly than those exposed to urban environments. Other psychological research has suggested spending time in nature increases attention and focus and reduces stress. These psychological responses are likely a result of human evolution, as Shultz described biologist E.O Wilson’s interpretation:
According to his ‘biophilia’ hypothesis, our brains evolved to process the stimuli our ancestors would have faced in nature, leading to a hard-wired disposition to respond positively to the natural environment. With brains less well suited to the sights and sounds of human-made environments, we may find these surroundings more stressful and tiring.
Schultz also tied natural surroundings to a lower risk of early death, a quicker recovery from injuries and lower blood pressure. There was even a study that related a decreased risk of depression, anxiety, asthma, diabetes, heart disease and respiratory infections to the amount of green space within one kilometer of a person’s home.
Clearly there are a multitude of public health benefits associated with an increase in green spaces. Water management and other city planning efforts, such as those currently underway in Baltimore and Philadelphia, are helping residents gain access to cleaner air and water regardless of economic status or location. And as more and more concrete lots and abandoned buildings are converted into parks and gardens, residents may even start to feel that they live in a city within a park, not the other way around.
Photo Credit: Sharat