“[By using] the Silva Cells, we were able to achieve several overlapping design and engineering goals [and] the maturity rate of trees and other herbaceous plants has been exponential, compared to similar sites without Silva Cell support.”
A central business district in North Bethesda, Maryland, Pike & Rose began a multi-phase revitalization project in 2011 with green infrastructure and sustainability at the forefront. The DeepRoot Silva Cell system provided several benefits to the project developers, including Maryland- and Montgomery County-approved stormwater management, the creation of large open tree-planting zones (to support large tree installation), and a thriving ecosystem promoting ongoing healthy tree growth by interconnected soil beds and sub-surface drainage and moisture retention – helping to make this development a successful, award-winning renovation community.
Number of Silva Cells: 315 3X (Phase 1) and 889 3X (Phase 2)
Amount of Soil Volume Per Tree: 43,000 ft3
Number of Trees: 11 trees (Phase 1) and 29 trees (Phase 2)
Type of Project: Integrated trees stormwater, mixed use, mall, residential, commercial
Project Engineer: VIKA Maryland LLC
Project Designer: Clinton + Ries
Project Contractors: Whiting-Turner and Ruppert Landscape
Installation Date of Silva Cells: July 2013 (Phase 1) and September 2016 (Phase 2)
Project Timeline: 2012-2018
In an effort to reinvigorate an area on the western side of Rockville Pike, defined by an aging strip mall, and draw new residents, developers and urban planners set out in 2011 on an ambitious upgrade project that emphasized green processes, beautiful landscapes, and open spaces for various forms of transportation.
This mixed-use community of apartments, offices, stores, restaurants, public spaces, and retail establishments was to feature sustainability as a key feature from the very start. Indeed, renewable energy has been integrated into the buildings from the top down, including rooftop solar panels and garden spaces. Likewise, Pike & Rose committed to their sustainability goals in their landscaping and urban forest elements as well, choosing to incorporate the DeepRoot Silva Cell to support soil volume, stormwater, and tree roots.
In addition to supporting the 40 trees lining over a dozen block faces, the DeepRoot Silva Cell also successfully cleaned area water in a completed paved environment. Getting the stormwater managed in this way was critical because the state of Maryland and Montgomery County have very stringent requirements, as the area drains directly into the largest estuary on the continent, the Chesapeake Bay. The EPA has designated that entire water system to be so vital that it was the first NPDES (National Pollutant Discharge Elimination System) Phase 3 watershed in the nation. For this project to go forward, DeepRoot obtained approvals from Montgomery County and the state of Maryland in a rigorous application process.
Because the area did not have adequate space for traditional large water gardens or retention ponds, the DeepRoot Silva Cell provided the Pike & Rose community with effective treatment of all water from the site, used to help support healthy tree growth. While the soil in the cells provides bioremediation, water in the soil is an essential resource to the trees – as they grow to maturity, evapotranspiration and canopy intercept of the water will increase as well, adding longevity and resiliency to the system, while simultaneously reducing maintenance. The net effect is the Silva Cell system reduces the stormwater flow, and delays, cleans, and cools the stormwater that does leave the site – meeting all the essential goals of the Chesapeake Bay regulators while reducing costs when compared to traditional systems.
According to the architects at Clinton + Ries Landscape, the Silva Cells did indeed provide a number of important benefits:
-Fulfillment of county greywater and stormwater drainage requirements
-Interconnected oil beds to promote tree and plant root growth
-The creation of large open tree planting zones to support large caliper street tree installations
-Sub-surface drainage and moisture retention for positive growth and reduction of irrigation needs
The design team goes on to say: “The past 5 years of maturing landscape has shown great success containing and keeping most rainwater runoff on-site for use by plants. The maturity rate of trees and other herbaceous plants has been exponential, compared to similar sites without Silva Cell support.”
Pike & Rose exemplifies sustainability throughout its community and sets a clear example of what is possible when longevity, aesthetics, and design are applied with equal priority. Pike & Rose achieved two notable USGBC LEED accomplishments:
– Pike & Rose itself is a LEED Neighborhood Development (ND) Stage 3 Gold-certified project, one of only four LEED NDs in the U.S. and one of five in the world.
– The project is one of only a few in the world to achieve LEED certifications at 100% of its buildings.
The area that was once 23 acres of asphalt is now covered with 21,000 cubic feet of green roof space, over 12,000 square feet of surface area of Silva Cells – housing over 43,000 cubic feet of soil volume to support tree growth, manage stormwater, and enhance green infrastructure. Silva Cells treat 100% of the stormwater onsite. The solar canopy is Maryland’s largest retail garage-top canopy.
The team behind Pike & Rose recognized the local community’s need for a walkable, sustainable place to live, work, and play. They used native plants, green roofs, and sustainable irrigation methods throughout the property. The landscaping at Pike & Rose is designed to reduce potable water consumption by 96% versus typical commercial landscaping.
These are just some of the reasons the project won the following awards in addition to being named the Best Sustainable Project of 2019:
– USGBC: National Capital Region’s Award for Innovative Project of the Year-Neighborhood Development
– National Association of County Planning Award of Excellence
– NAIOP Best Retail Project Street Level Retail Space of Larger buildings or Mixed-Use Award of Excellence
– NAIOP Best Mixed-Use Project Award of Merit
– National Association of Landscape Professional (NALP) and Landscape Contractors Association (LCA) award-winning project
Today, 10 years after construction began, we can see that Pike & Rose is a vibrant, transit-oriented neighborhood that exemplifies the value that sustainable development can bring to a project and how it impacts the lives of the community it serves.
Feature image courtesy of Federal Realty