The National Building Museum (NBM) held a session on the Sustainable Sites Initiative, which outlines voluntary national guidelines and performance benchmarks for sustainable land design, construction, and maintenance practices. Nancy Somerville, CEO of ASLA, said the Sustainable Sites Initiative focuses on the “connective tissue between buildings” and will fill gaps in the existing rating systems, including LEED. The Sustainable Sites Initiative will be integrated into LEED (and be a part of its “bookshelf” system), and also serve as a stand-alone rating system. The final draft report will be released Fall 2009, followed by a call for pilot projects designed and built using Sustainable Sites’ pre-requisites and credits. The full rating system will be rolled out in a few years.
Jose Alminana, ASLA, Principal, Andropogon: Alminana explained the importance of the Sustainable Sites Initiative. Alminana argued that “blue is the new green,” and highlighted figures that show humans rely on one percent of the earth’s water for all their needs. As a result, buildings and sites need to be re-thought in terms of their water use. Green sites can cut down water and energy use, C02 emissions, and the amount of solid waste produced. Alminana also said “buildings need to be alive,” and “built environments need to be built like a tree — they must regenerate, renew and restore.” Alminana highlighted Berlin’s “biotrope ratio,” (Berlin has among the world’s best ratios of green space to built environment), as well as Seattle’s Green Factor, as examples of cities creating productive environments.
Alminana highlighted projects that exemplify Sustainable Sites principles and credits. First, Alminana focused on a key principle of Sustainable Sites: “Provide regenerative systems for inter-generational equity.” In other words, use restorative design to create living buildings and leave a positive legacy to future generations; don’t consume all resources now. Alminana argued that sustainable sites must regenerate, produce, upcycle. “All sites, even brownfields, can provide ecosystem services.” The Sustainable Sites Initiative will aim to protect and enhance ecosystem services, while minimizing the use of materials.
In an example that highlights one of the “potable water” credits in the Sustainable Sites Initiative, Alminana pointed to a project for Thomas Jefferson University’s Lubert Plaza, which “reconnects to the natural water cycle” by using water from the roof of the building, and air conditioning condensation, to irrigate a nearby park. “Trees act as pumps” and circulate the water through man-made soil systems layered to help move water. This complex system resides above a parking garage, so is, in effect, a green roof park. In an example of the “manage water on-site / clean water on-site” credits, the Sidwell Friends School in Washington, D.C. uses a man-made wetland system to recycle, cleanse, and re-use water. (see a great post on this by Pruned). Sidwell Friends School said they wanted the “best use of water resources,” and the “productive use of all land” in their site. As a result, the building and site work together — there was “total equal collaboration.” Sidwell Friend’s building dashboard is used to monitor performance.
Susan Olmsted, ASLA, Architect and Landscape Architect, Mithun: Olmsted asked: “How do you develop urban areas without compromising the ecology and degrading existing ecosystem services?” In projects Olmsted has worked on with Mithun, project teams often map solar energy budgets, water, and habitat by examining what the ideal, “pre-development conditions” would be like, and then test the effects of various designs on these conditions. Olmsted said waste water was particularly expensive to deal with — there is a cost for bringing clean potable water in, and then removing used water, so consumers often effectively pay twice for water usage. As a result, re-using groundwater and limiting potable water usage is always a goal. Stormwater, which is also costly for cities to deal with, can be addressed through bioswales or stormwater basins. Olmsted also recommended resource management associations for “integrated design” green developments, so communities can get involved in keeping their integrated design systems working well.
All speakers discussed how to get to a carbon-neutral site. Alminana argued that peatlands and wetlands are the greatest carbon sinks. With a carbon tax, or trading system coming into place, “it’s only a matter of time before ecosystem services will have a financial value.” As a result, developers and users of landscapes need to create economic analyses involving the maintenance costs and carbon sequestration rates of different types of landscapes. For example, forests are more complex systems to set-up, but have lower maintenance costs over time, and higher C02 sequestration rates. Bioswales, while providing important stormwater management services, are higher-maintenance.
Also, Alminana asked: “should we restore to the past, or restore to the future?” Current systems are centralized. However, “nature doesn’t work this way. Nature de-centralizes and is self-sustaining.” Alminana argued cities, in turn, also need to de-centralize their infrastructure, trace inputs and outputs, and re-make cities so they work through an integrated, natural design. “Drains are unreal.” Water infrastructure, the transmission lines for waste water, costs 5-6 times more than an wetland system, and produces C02 emissions. A paradigm shift is needed in infrastructure.
Learn more at the Sustainable Sites Initiative, an inter-disciplinary effort led by the American Society of Landscape Architects (ASLA), U.S. Botanic Gardens, and Lady Bird Johnson Wildflower Center. Sustainable Site Initiative stakeholder groups include the U.S. Green Building Council, Environmental Protection Agency, the Nature Conservancy, and a range of other organizations.
Also, check out an interview with Jose Alminana.
Image credit: Andropogon Associates