A prevalent problem facing cities and regions is inadequate stormwater infrastructure. Sixteen billion gallons of raw sewage get dumped into Philadelphia’s rivers and streams each year after rain events. Because wet-weather flow is a dispersed problem, it has become increasingly clear that it requires a dispersed solution. Consequently, cities have started to explore alternatives for stormwater capture and treatment that are decentralized and incremental, rather than a system-wide upgrade. Individual lots in aggregate can have a significant impact on water quality. With funds being directed towards infrastructure rather than recreational or public space per se, we must explore creative ways to use infrastructural improvements as open space amenities.
This project explores the efficacy of customized substrates to develop alternatives to conventional on-site stormwater collection. Utilizing digital modeling and computer-controlled fabrication, we were testing whether or not manipulating geo-cells (three dimensional in-grade structures filled with gravel, soil or plants) can produce innovative infiltration features that combine their functional requirements with a visibly expressive surface that can add color, pattern and texture to vacant sites. Geo-cell configurations are currently limited by their uniform geometry. By varying the cellular shape, density and profile, we can fabricate them to produce a greater degree of variety and thus be more responsive to the opportunities of small urban sites.
The customized geo-cell configuration was developed using parametric software to visualize existing and redirected water flow patterns. These patterns helped determine the geo-cell size and distribution of material mixtures between planting and gravel. The prototype tested the use of both conventional and alternative plastics. Test plot 1 was fabricated using petroleum-based plastics common to geo-cells. The second test plot, however, was fabricated using newer compostable corn-based plastics (polylactic acid biopolymer by Natureworks). PLA is becoming more readily used in the packaging industry. Its use, however, had not yet been extended to customized exterior applications using laser fabrication techniques.
Project: Self-initiated research exploring customized geo-cells.
Date July 2011
Size 2,000 sf
Location Philadelphia, PA
Project Team Karen M’Closkey, Keith VanDerSys
This research received a 2011 Boston Society of Architects Research Grant and a University Research Foundation (URF) grant.