We’ve been feeling the effects of climate change a lot lately—drought in California, record highs of up to 120 degrees Fahrenheit in Arizona, hurricanes and superstorms—to name just a few. Atmospheric scientists now say the carbon dioxide levels may have permanently surpassed 400 ppm. It’s safe to say this bad weather is probably only going to get worse.
With this in mind, the American Society of Landscape Architects (ASLA) recently released a guide on resilient design, aimed at helping communities better weather these events, and rebuild quicker when destruction does happen. To quote from the press release, it “includes numerous case studies and resources demonstrating multi-benefit systems as well as the small-scale solutions that fit within those. The guide also explains landscape architects’ role in the planning and design teams helping to make communities more resilient.”
Ultimately, the guide emphasizes that “working with nature, instead of in opposition to it” is the way forward. Much of our current large-scale infrastructure (think walls, dams, and sewers) is ill-equipped to handle today’s extreme weather, and is only becoming more expensive to build and maintain. Resilient landscape planning offers ways to mitigate these threats in a multi-faceted way as opposed to the traditional single-solution approach which, when it fails, offers no backup.
The guide is organized around six types of natural disasters. Each section discusses how resilient design can be used, outlines some co-benefits (part of the strength of these techniques comes from the fact that many play more than one role, or can have more than one impact), and details more specifically how landscape planning can be used in implementing a design. This portion of the guide is fairly brief, but is bolstered by a number of case studies and other resources.
Resilient planning to support biodiversity emphasizes the important role that varied species—both flora and fauna—play within an ecosystem by enhancing the services that it provides. Some possible approaches include habitat restoration, planting with biodiversity in mind, and building wildlife corridors.
Planning for drought takes a number of different approaches, from utilizing gray water for watering lawns, to landscaping with drought resistant plants, to designing to best capture and direct precious water resources.
Design approaches to dealing with extreme heat mostly center around vegetation; planting and maintaining a tree canopy, and increasing green wherever else possible, such as green roofs and alleys.
Before (2007) and after (2013) comparison of a NYC Parks Green Roofs Project. (Credit: NYC Parks Green Roofs)
Fires are a significant threat and are perhaps the most difficult to plan for out of all of the disasters discussed. Planting fire-resistant vegetation can help, and landscape design can be used to create “defensible spaces” to help slow or stop a spreading fire.
Resilient design offers a few approaches to planning for flooding, including preserving riparian areas and ecosystems to act as buffers or channels, and designing parks and other green space to capture, hold, and filter water.
Cromwell Park in Shoreline, WA can hold an acre-foot of water (almost 435,000 gallons), enough to eliminate the neighborhood flooding problem. (Credit: City of Shoreline)
Proper design and planning is key to preventing landslides. Working with the natural contours of the land, utilizing vegetation and root systems to combat erosion, and carefully selecting or even strengthening the soil can all help lessen this threat.
The resources offered range from federal research and guides (such as from EPA and NOAA), to interviews with experts in each topic, to National Geographic articles. Perhaps even more useful are the case studies, which include everything from site-specific project pages to city-wide master plans. ASLA has created a guide that has a lot to offer in the way of inspiration and direction for those looking for ways to start planning for the future.
Filed under: green infrastructure, maintenance/management, planning | Tagged: ASLA, biodiversity, design, drought, erosion, fire, flooding, heat, heat island effect, landscape architecture, landslides, planning, resiliency, urban development, urban planning, urban trees | Leave a comment »