Getting to Green 2020: Soil – The Foundation for Green Infrastructure
Nature has Designed a Partnership between Land and Water
In November 2010, the British Columbia Landscape Architects Architects Association hosted a Landscape Café in Vancouver. Featured speaker Peter MacDonagh discussed the importance of restoring and protecting healthy soils as the foundation for green infrastructure.
“With increasing development, impervious area, and water and air pollution, soils become increasingly important in urban areas,” states Peter MacDonagh. “Key functions provided by soil include holding rain that falls on the soil as well as surrounding impervious surfaces, filtering pollutants out of stormwater, and providing rooting structure for vegetation, which in turn provides benefits, such as, for example, evaporative cooling that reduces the urban heat island effect, air filtering, additional stormwater cleansing and interception, as well increased property values.”
Mr. MacDonagh showed a number of case studies that highlighted the importance of soil in green infrastructure, including:
- Lakeshore and stream soil bioengineering projects that protect soil by stabilizing shorelines with deep-rooted native plants and natural channel design
- Stormwater wetlands that detain and filter large quantities of stormwater
- Raingarden projects that hold and filter stormwater on a smaller scale
- Green roof projects, which provide an absorbent layer on roof surfaces where space is not available at grade and also double to triple roofing membrane lifespan, as well as reduce building cooling needs.
- Urban forest projects that grow large trees and intercept as well as treat stormwater, even in urban areas dominated by paved surfaces, by providing large rooting volumes under suspended pavements.
All of these projects also increase aesthetic value as well as wildlife habitat value.
Getting to Green 2020
“Getting to Green 2020” is a set of goals to propel Vancouver to the top as the World's greenest city. In 2010, Mercer's ranked Vancouver as the world's #13 EcoCity. Green Infrastructure is heavily featured.
The Urban Forest goals for 2020 include the following: “the world's most extraordinary urban forest” & “150,000 new trees planted within the city”.
To Learn More
For an overview of the Landscape Café, click on Soil – The Foundation for Green Infrastructure. Any city that intends to thrive in a diminished oil and changing climate future will need to husband its soil resource, diverse perennial vegetation and the moisture which keeps it healthy.
About Peter MacDonagh:
Peter MacDonagh co-founded and is the Director of Science and Design of The Kestrel Design Group in Minneapolis, Minnesota. A native of Ireland, he is a recognized authority on sustainable landscape architecture and soil bioengineering, and is widely sought for his expertise in urban stormwater, green roofs, and urban trees.
“These days we’re all hearing about 'Green', but few people realize to be really 'Green' you must be 'Blue' too! Nature has designed a partnership between land ('Green') and water ('Blue') where each benefits the other,” states Peter MacDonagh.
Posted December 2010