Resource: Liberty Lands

Print Background Essay

In the last thirty years, many factories, industrial plants, and military bases shut down or moved, leaving behind vacant properties. The old, abandoned land often was contaminated with harmful chemicals and biological pathogens, making it unsafe and unusable to the community. This kind of site is commonly known as a brownfield.

Currently, there are land reclamation groups working to recycle brownfields by converting the contaminated, hazardous land into clean, safe, usable land for city dwellers. In order to recycle these contaminated sites, clean-up teams take four key steps: they assess the site's damage; work to prevent further contamination; clean up the hazardous materials; and, then, design plans to re-use the land.

Biosolids can play a key role in the recycling and re-vegetation of brownfields. Biosolids are nutrient-rich, organic materials that come from the treatment of sewage at a water treatment facility. Billions of gallons of wastewater can travel to a facility each day from homes, businesses, and street runoff. The wastewater contains solid material and pollutants, for example food particles, human waste, oils, and chemicals. A series of physical, chemical, and biological steps treat and clean the water and filter out the biosolids, which are then used as fertilizer to improve soil and stimulate plant growth. The processed water, called effluent, is released back into the environment.

The Liberty Lands project in northeastern Philadelphia demonstrates how recycled biosolids are used to improve a piece of land. The project began when an abandoned industrial site, previously known as the American Street Tannery, was donated to the Northern Liberties Neighbors Association in 1995. Members of the community hoped to create a multi-use open space for the public. Once the pollution from the tannery was cleaned up and contaminated materials were removed, biosolids were used to improve the quality of the land. The organic matter found in biosolids is rich in nutrients, so it acts as a natural fertilizer. As a result, the soil is able to retain more water and nutrients, which supports plant growth.

With the help of a grant from the Philadelphia Urban Resources Partnership, the resulting two-acre park, called Liberty Lands, features community garden plots, a farmers' market, artwork, and space for events. The park is open to the public and hosts a variety of community events, helping to revitalize the community. Liberty Lands is still managed by the Northern Liberties Neighbors Association without any financial support from the city, but additional grants from organizations help maintain and improve the site.

To learn about conserving top soil, check out Organic Farming: Conserving Top Soil QuickTime Video.

To learn more about recycling, check out Visiting a Recycling Plant QuickTime Video.

Print Questions for Discussion

• What were the major actions taken to transform the abandoned industrial site into a park?
• How did scientific knowledge play a role in creating Liberty Park?
• How did they improve the soil near the old tannery to help it grow grass and trees?
• What technologies and natural processes are used to convert wastewater to useable biosolids?
• Why don't we want nitrates and phosphates in our bodies of water? Where do these pollutants come from? How is it possible that something is an environmental contaminant in one context, but desirable in another?