Ecosystem Services in Tacoma

Walking through Point Defiance Park on one of Tacoma’s rare sunny days, a visitor will see children playing, joggers and bikers getting fresh air and exercise, and couples enjoying the variety of roses flourishing in the gardens. The scene is one of family bonding and health, but also of extensive economic value.

The parks of Tacoma, run by Metro Parks, provide residents of Tacoma and the surrounding areas with hours of recreation and activity, but also what are called “ecosystem services.” The combination of these two assets make these parks worth millions of dollars, an amount quantified in two reports, one by Metro Parks and the other by Earth Economics.

“Tacoma has high quality parks,” said Zac Christin, a research analyst for Earth Economics and head researcher on the Metro Parks study.

Earth Economics is a nonprofit agency that provides economic analysis of ecosystem services. Their Economic Impact of Metro Parks Ecosystem Services Study found that MPT provides 3.6 million to 13 million in ecosystem services and approximately 18.2 million in social capital, education, and health benefits.

“These services were recognized prior to the report,” said Christin, “The biggest ones are aesthetic and recreational value.”

Parks provide opportunities such as hiking, biking, swimming, kayaking, and running. Over half of Metro Parks contain forests and extensive trails. While the research methods to put a dollar amount on the social benefits of open green space are still developing, studies do show that children who are exposed regularly to the outdoors and green spaces do better on tests, and have a lower likelihood of ADHD.  People are also more likely to meet health standards when they live in areas with park amenities.

“People evolved in nature, and if you have nature around you, it keeps you sane,” said Kathy Sutalo, Metro Parks Urban Forester.

Therefore, if a city has exceptional parks, it becomes a more attractive place to live, which reduces suburban sprawl, the converting of useful land into housing. The more people are spread out, the more resources are used, and there is less land available for timely production and farming.

Phase I of the Economic Impact Study, done by Metro Parks itself, demonstrated that Tacoma does indeed have exceptional parks, in comparison to those within surrounding areas. On any given day, two-thirds of the people occupying one of Tacoma’s popular parks are not Tacoma residents. Not only does this add value to the parks themselves, but it generated 27 million last year in money visitors spend within the city.

The value of the parks, however, is not limited to their beauty and appeal. Green spaces provide services that, had the city to pay for them, would cost extensively more than does the maintenance of a well established park.

Washington’s famous evergreen trees are one major reason for this; Tacoma alone has 5,200 trees of various types. They provide shade, which lessens the effects of global warming, they turn carbon dioxide into oxygen, which reduces pollution, and they provide a habitat for various animal species that could not otherwise exist in such a large city.

“Trees are the anchor,” said Sulato. “You are better off with trees and no shrubbery than you are with shrubbery and no trees.”

Maintaining a large diversity of shrubbery and greenery is also important however, because it wards off the development of invasive species. When settlers began developing Tacoma, they cut down most of the trees; when a tree is removed from an urban area native plants were overcome by species such as blackberry and ivy. Native greenery such as grass makes parks the most absorbent areas in the city, regulating storm water, and keeping the city from spending millions to divert it elsewhere.

Once parks, such as Point Defiance, have developed a substantial base of native species, they are able to almost entirely regulate themselves; however, maintaining less developed parks is expensive and hard work. Fortunately, Tacoma has a large force of willing volunteers who, last year alone put in 170,000 hours of volunteer work, generating great worth in social capital, which is the benefits gained by engaging in the community.

Engaging people in the parks is part of why MPT commissioned these studies.

“We want to let people know that parks aren’t just pretty,” said Sutalo.

The studies have helped the city raise awareness of how many amenities parks provide, but the ultimate goal is to help them understand that parks are just as important to a city as streets and sewers.

“We want to make Tacoma the place where benefits are integrated and understood,” said Sutalo.

While the studies helped to make people more aware of what Tacoma does have, it also raises awareness as to what sort of tools are missing.

“It inspires them to recognize what kind of information we still don’t have,” said Roxanne Miles, Community Development Manager.

In the future, she hopes there will be ways to quantify and place economic value upon things such as families playing together and a healthy childhood.

There is a myriad of research to be done in the future. However, for now, what is known is that parks and green spaces hold a high economic value.