From Jason King’s Landscape+Urbanism site
An amazing resource posted on ASLA’s The Dirt (here) focuses on Design Guidelines for Urban Wetlands, specifically what shapes are optimal for performance. Using simulations and physical testing to investigate hydraulic performance the team from the Norman B. Leventhal Center for Advanced Urbanism (LCAU) at MIT. Led by Heidi Nepf, Alan Berger and Celina Balderas Guzman along with a team including Tyler Swingle, Waishan Qiu, Manoel Xavier, Samantha Cohen, and Jonah Susskind, the project aims to have a practice application in design guidance informed by research. From their site:
“Although constructed wetlands and detention basins have been built for stormwater management for a long time, their design has been largely driven by hydrologic performance. Bringing together fluid dynamics, landscape architecture, and urban planning, this research project explored how these natural treatment systems can be designed as multi-functional urban infrastructure to manage flooding, improve water quality, enhance biodiversity, and create amenities in cities.”
Starting in the beginning by outlining ‘The Stormwater Imperative’, the above goal is explained in more depth, and issues with how we’ve tackled these problems are also discussed, such as civil-focused problem solving or lack of scalability, but also explore the potential for how, through intentional design, these systems “can create novel urban ecosystems that offer recreation, aesthetic, and ecological benefits.” (1)
The evolution that has resulted in destruction of wetlands through urbanization, coupled with deficient infrastructure leads to issues like flooding, water pollution due to the loss of the natural holding and filtering capacity of these systems and the increased flows. However, as pointed out by the authors, this can be an opportunity, as constructed wetlands “can partially restore some lost ecosystem services, especially in locations where wetlands do not currently exist.” (5)
The modeled flow patterns are also interesting, showing the differentiation from fast, regular, slow flows, along with any Eddy’s that were shown in dye testing using the flumes.
Check it out and see what you think. The report is available as a online version via ISSUU or via PDF download from the LCAU site, where there are also some additional resources. All images in this post are from these reports and should be credited to the LCAU team.