The Silva Cell is a patented modular suspended pavement system that holds unlimited amounts of lightly compacted soil while supporting traffic loads beneath paving. That soil serves two important functions: growing large trees and treating stormwater onsite. Interception and Evapotranspiration Large trees intercept and evapotranspire significantly more rain than small trees. For example, a healthy 40 year old Hackberry tree is estimated to provide 14 times as much interception as a 10 year old Hackberry (McPherson et al 2006).
Long-Term Infiltration As roots grow and then decay, they leave open channels in the soil that restore and/or enhance porosity and infiltration rates. Several studies have found a significant increase in saturated hydraulic conductivity in bioretention with plants as compared to those without (e.g. Lucas and Greenway 2011).
Water Quality Benefits Vegetation is crucial to many water quality benefits, including removal or sequestration of dissolved nutrients, hydrocarbons, and Total Suspended Solids (TSS).
Plants also slow water flow, allowing more time for sedimentation to occur (Hunt et al 2012).
Silva Cells can be used on almost any
type of site, including:
- Parking areas
- Green roofs/on-structure
- "Break-out" zones
Unlike some bioretention systems,
which leach nutrients and
negatively impact receiving water
bodies, Silva Cell systems also provide
nutrient removal. Additional lowimpact
development benefits of the
- Water quality
- Peak overflow reduction
- Low/no maintenance
- May use any type of soil
- Efficient use of space