The DeepRoot Silva Cell
Integrating Trees, Soil & Stormwater for Sustainable Development.
Photo courtesy of James Urban
“Nearly all of the associated problems result from one underlying cause: loss of the water-retaining and evapotranspirating functions of the soil and vegetation in the urban landscape.”
EPA commissioned report Urban Stormwater Management in the United States, 2008.
What’s missing from this picture?
It’s all about soil...
General Design Goals
Water quality and Water quantity
1. Volume and time water is held at the site
2. Increase infiltration and evapo-transpiration to reduce overall surface runoff
3. Reduce pollutant load
4. Reduce water temperature
Check dams
Rain Garden Case Studies
Surface water infiltration – Absorbing soils in planted areas or pervious pavers, and green roof areas.
Pavers and green roof approach is expensive.Limited by infiltration rate of soil and subsoil. Limited storage
How can we start to solve some of these problems?
• Large trees
• Treating stormwater as a resource
• Integrating trees, soil and stormwater
Grow big trees. Manage rainwater. Do it all on-site.
Pervious Pavement is the simplest way to get stormwater in to Silva Cells for storage and treatment
Perforated distribution pipe is installed to bring water from the catch basin through the Silva Cell system
Queensway Installation
Catch Basin
MMarquette Street, Minneapolis
Combined rain garden and below paving treatmentIn a suburban strip development
LR
Large Canopy
How much soil does a tree need?
Summary
PondsCisterns
Green roofsPervious pavers
Rain gardens Biofiltration with trees
Cities must employ all of the design options
Basic Applications
Streetscapes/Plazas
Break-out zones
Parking lots
Green walls
Green roofs/on-structure
All of these applications can be modified to optimize tree growth or stormwater management.
Parking Lot application
Use Silva Cells in parking lots to achieve green canopy cover goals and downsize the stormwater system without compromising parking spaces or utilities.
Wal-Mart SuperStore Parking LotLakeland, FL
Parking Lot application
Image courtesy of Bartlett Tree Research Laboratory (North Carolina)
Research shows trees grow best in uncompacted soil
Flexible and modular.