If it weren’t for us, bison and beavers might still roam Chicago, Illinois, the location of the ASLA 2015 Annual Meeting and Expo. The absence of these keystone species, which once provided important roles in the continental water cycle, represents a marked shift in ecosystem functioning. However, landscape architects and engineers from Andropogon Associates and Biohabitats are thinking about how to bring back the ecosystem services these species once provided in order to more sustainably manage water.
“We’re not bringing bison back to the edge of Chicago where they would have been, but looking at their functionality, the lessons that can be learned from them,” said Keith Bowers, FASLA, president of Biohabitats. “We need to ask ourselves how we can turn it around and be these species.”
One way to start this process is by “thinking like a watershed,” Bowers said. “How different would our water management systems be if our states were configured around our watersheds?,” he asked. While humans have made political boundaries irrespective of these watersheds, ecosystems – and their associated wildlife – simply don’t follow suit. The divide between human perception and ecological realities is ubiquitous. Just as an example, 73 percent of people polled in Baltimore, Maryland, do not believe they live in a watershed. This misconception is even more present in other parts of the country.
Thinking like beavers or bison in their native watersheds could provide solutions. Bison, for example, create holes, or “wallows,” in the ground that are perfect for collecting rainwater. Beavers also play a critical ecological role by building dams, which increase riparian habitat and can help store millions of gallons of water underground, among other benefits. Perhaps one way for California to adjust to drought would be to think more like these creative animals, “with their small, highly-distributed water management systems” that are more aligned with the functionality of a watershed. Their smart approach is the “the exact opposite of water engineering that happens in California,” said Erin English, a senior engineer at Biohabitats.
Thinking about how nature functions on the molecular level can also offer solutions said Jose Alminana, FASLA, a principal at Andropogon Associates. It’s at the molecular level “where life starts and where the future of the life on this planet will reside.”
Both Andropogon and Biohabitats have been leading the charge in designing landscapes that think like watersheds. The new U.S. Coast Guard Headquarters in Washington D.C. designed by Andropogon Associates and HOK was highlighted. This constructed landscape uses gravity and a set of planted terraces to move and cleanse water.
Mimicking nature’s functionality creates opportunities for more sustainable urban water management. Bowers said “we have to make that a priority.”