Reflections from recent trips across Southeastern Pennsylvania:

Communities are increasingly forced to deal with the long-term impacts of industrialization, where the veneer of economic prosperity ultimately gives away to reveal damaged communities and impaired ecological processes. We visited two sites that are deploying strategies to deal with such post-industrial conditions. One location was Palmerton, Pennsylvania; a Superfund town nestled in the bucolic backdrop of the Kitatinny Mountains. The other was Philadelphia’s Mill Creek, which is currently encapsulated within enormous sewer pipes underneath the city. The sustainable practices at Palmerton and Mill Creek provide some insight on how to design strategies that restore the ecological functions of highly impaired environments.

Palmerton Superfund Site

In 1898, Palmerton was founded as a factory town, nestled between two ridgelines, to conduct zinc smeltering during the height of industrialization in the United States. After decades of constant smeltering, the forest ecosystem collapsed, affecting an expanse of nearly 2,000 acres. Due to deposition of zinc, lead and cadmium from the furnaces, microorganisms in the soil substrate were killed off, and an integral component of the forest lifecycle ended. Without decomposers, nutrients in the soil were eliminated, leading a domino effect that decimated the forest. To date, it is the largest Superfund site east of the Mississippi River.

On site, I was struck by the eerie landscape of windswept, bleached trees amongst barren grounds of dry dirt. Abandoned, rusted factory facitilies stood like sentinels to remind residents and visitors of a foregone era. Amazingly, some plant and wildlife species are returning to the environment; numerous sprouts of sassafras and sourgum were seen emerging from gnarled trunks.

Due to the immensity of the contaminated area, removing the toxic substrate was out of the question. We learned about two strategies to rebuild the soil nutrients, with the goal of creating a capping layer of substrate above the contaminated soils. The first attempt to “green” the decimated slopes entailed terracing the mountain to establish over 60 miles of roadways. These costly roads provided access for trucks to spray “ecoloam” along the slopes. Ecoloam was an engineered growing medium composed of sludge and schlag material from city waste. From afar, this method successfully “greened” the mountainside. However, some critics of this method blame the pervasive amount of invasive species on the applied slopes, due to the unpredictability of the seed composition of the ecoloam mixture. Additionally, trees could not establish beyond the depth of the ecoloam because the roots would hit the contaminated substrate beneath.

The land now belongs to telecommunications monolith known as Viacom, as a side acquisition through various transactions. To its credit, Viacom is funding the implementation of the second strategy, which relies on the hardiness of warm season native grass species to restore and stabilize the mountain slopes. Based on a serpentine barren-type ecology, this strategy aims to mimic the type of succession that had occurred in the site’s geological glaciation context. To establish the grasses, a growing medium composed of limestone, commercial fertilizer, grass seeds and compost was sprayed from the air, or hand-dropped along the slopes. This method appears to be less disruptive of the mountain slope because roads are not necessary, and the warm season grasses seem to be growing quite successfully.

In addition to the warm-season grasses, the predominant plant species we observed included the gray birch, sassafras, poplar, aspen and chestnut oak trees. Furthermore, some rare plant species were thriving quite well in these extreme conditions, such as wild bleeding heart and sandwort. Despite the calculated efforts to establish native plants, invasive species continue to pose a threat to the restoration efforts. As such, the staff work hard to eradicate the butterfly bush and ailanthus tree that they find along the slopes.

Mill Creek, Philadelphia

Mill Creek is exemplary of how industrialization and the fast densification of urban areas impact watershed ecology. Mill Creek is one of hundreds of streams that were channeled and buried into Philadelphia’s combined sewer system. Tracing the journey of Mill Creek from upper Merion to its confluence with the Schuylkill River in Philadelphia was a fascinating excursion. Unaware of the negative ecological impacts of channeling Mill Creek into the sewer system, the city of Philadelphia filled in the stream valley with fly ash to provide ground foundation for more development. Eventually, the ash compressed and significantly destabilized the foundation, leading to the collapse of several neighborhood areas along the historic streambed.

Photo credit

As we traveled across West Philadelphia, following the historic streambed, we visited sites that are employing various sustainable initiatives to improve storm water quality, among other issues. As a landscape architect, one can conceptualize these efforts as ways to measure, or index, the historic stream path. Gardens, tree plantings, swales, retention systems, and rain gardens not only mark the path of the stream, but also restore some ecological functions of the watershed. These interventions can bring new life back to the over-developed, impervious surface of urban areas.

One such intervention is taking place at a community garden called Mill Creek Farm. The site, located above the Mill Creek historic streambed, originally had row houses built on top. When the foundations collapsed, local residents took over the empty lot by starting a vegetable garden. Today, two dynamic young women manage a portion of the farm as a non-profit. In many ways, Mill Creek Farm reminded me of the community gardens that I had volunteered with in Detroit. Like the network of urban gardens in Detroit, Mill Creek had a strong educational component in which urban youth were provided direct, hands-on experiences with the land and sought to increase food security and nutrition in urban settings. Spanning half a city block, Mill Creek Farm was packing a high concentration of programming into its operations, including a green roof demonstration project, nutritional workshops, public art, a composting toilet, beehives, and organic gardening practices.

Mill Creek Farm is located on property owned by the Philadelphia Water Department, which is central to a lot of this initiatives in the city. PWD has highly innovative approaches to dealing with water issues in the city, and Mill Creek Farm is one manifestation of their vision. These practices included a “hybrid sewer system” next to the Blackwell housing development in West Philly, which entailed an underground water retention system that would retain water for a period of time. We also examined a basketball court that used porous asphalt. An overflow swale was constructed at the edge of the court to account for excessive runoff that would lead to a drainage pipe. At Clark Park, one can almost imagine a time when Mill Creek formerly flowed freely in this area. Today, portions of Clark Park experience drainage issues, evidence of former mill ponds. Nearby, a native plants demonstration garden stewarded by USP adds an accent of greenspace in the area. Unfortunately, it was fenced off and inaccessible to the public.

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We currently live and operate in a condition that is forcing us to deal with the ramifications of industrialization that built a petroleum-dependent economy and society. These impacts have negative effects on our ecosystems, community structures and social cultures. These two trips afforded a sense of potential for landscape architects to become proponents of positive impacts, providing a framework for design solutions to our damaged world. Perhaps the solution lies in the synthesis of many solutions. Palmerton and Mill Creek initiatives are demonstrating that life after “death” can take place, where nature and humans are no longer opposing forces, but a symbiosis of processes that can sustain a better quality of life for future generations.

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  1. thegirlworks

    Great post. Now I know what I missed on the Wednesday field trip…
    Amy




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