State Street Portsmouth NH - An Example of Leadership in Green Urbanism

It is often what you don't see that is the most interesting, and this is the case on State Street in Portsmouth. Next time you are walking down one of the sidewalks and pass a new street tree, stop and think about what lies below the brick. One of the many "Green Ubanism" design details developed by the project's landscape architecture firm, Ironwood design group http://www.fewood.com/  was to integrate a new product Silva Cell  into each street tree planting pit to ensure a sustainable future for the street trees. State Street is only the second project in New England utilizing Silva Cell's (the first was Union Street in West Peterborough, NH, also an Ironwood design group project)

The Silva Cell is a modular subsurface integrated tree and stormwater system that holds unlimited amounts of soil while supporting traffic loads beneath paving and hardscapes.The Silva Cell meets H-20 loading standards and can be used in a wide variety of tree and stormwater management applications of any size. They make 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 on site. The integration of green utilities like soil, trees and water into our urban areas substantially improves their design sustainability and helps alleviate some of our most pressing ecological challenges – including air and water quality, rising temperatures, flooding and erosion from daily rainfall events. Ironwood design group, a landscape architecture, urban design, and environmental planning firm providing superlative design to projects throughout New England from a studio in Exeter, New Hampshire http://www.fewood.com/