The Australian Institute of Landscape Architects just announced their 2008 National Award winners, and I spent some time perusing through them last night. There's lots of EDAW in there, incidentally. Anyhow, the one that I was most interested in was project by Urban Initiatives that developed a wetland infrastructure design for the Kubu River Hippos' Exhibit at the Werribee Open Range Zoo. Traditional zoo water enclosures use a huge amount of energy in their constant water recirculation, and Urban Initiatives came up with a bio-filtration system that not only provided a more energy efficient solution but also helped connect the design conceptually to the Okavango Delta wetland in Botswana that is the natural habitat of the hippos housed in the exhibit. Here's a constructed view of the wetland followed by a design diagram of the system:
Now, the rest of the exhibit starts to look like Disney's Jungle Cruise Adventure as they delved into replicating some of the human cultural elements of Botswana region, but I guess zoos aren't that far away from theme parks to start with.
Anyhow, this project's water filtration system connected with my interest in this type of plant-based human infrastructure. It's a popular landscape architecture topic these days as cities try and tackle non-point source water pollution. Portland, OR is the poster child for this with their Sustainable Stormwater Management Program. But while you see bio-swales (aka. planted water filter ditches), water quality ponds (aka. larger planted stormwater holding basins) and the like all over the place, few places take the infrastructure to that next level, such as purifying sewage. And the hippo pond is, of course, treating a lot of hippo poop. When I was in Spain last year I picked up a book called "Waterscapes" by Helene Izembart and Bertrand Le Boudec that presents a lot of conceptual examples and specific case studies of mainly European projects that use plants systems to treat wastewater. So, if the hippos example interests you, I recommend checking out that book.