Several MLTnews readers had been concerned that all the trees in the transit center upper parking lot were being removed during the repaving project. It is true that they have been removed, but they are being replaced with new trees in special planter boxes that will help prevent future pavement damage while cleaning runoff from the parking lot:
The Contractor mobilized equipment to the site, and began site work by removing the existing trees in the parking lot area. Many of the trees were diseased or had caused pavement damage. However, new trees will be planted as part of the Restoration Project. In fact, planting of the new trees will feature an innovative technique to better protect the tree roots, treat stormwater, and, at the same time, preserve the pavement. The technique calls for using special “root boxes”, in this case a product called Silva Cell. (This product was installed at the Olympic Village in Vancouver in 2007 and awarded a LEED-ND Platinum Certification.) Each Silva Cell is a subsurface integrated tree and stormwater system that holds unlimited amounts of soil while supporting traffic loads beneath paving and hardscapes. Silva Cell makes it possible for streetscapes, plazas, and parking areas to support healthy, thriving trees without compromising above-ground surface areas. The healthy soil housed within the Silva Cell serves two important functions: growing large trees and treating stormwater onsite. Next week the Community Transit’s contractor will begin excavation for the Silva Cells to be installed. 14 new trees will be planted prior to the parking overlay and sealcoat process.
Here is a video of a Silva Cell installation in a similar project in Florida: