Going Green from the Ground Up
- May 19, 2008
By Jo Ann Jarreau, ASLA, LEED AP, Jarreau Inc.Consumers have reached an environmental turning point. According to the latest research, the vast majority is “seriously concerned” about the environment and believes that a company’s environmental practices are important in making key purchasing decisions. For builders and property owners who can prove a commitment to sustainability, this means a leg up on the competition with these savvy consumers. If your projects are using the U.S. Green Building Council’s (USGBC) voluntary Leadership in Energy and Environmental Design (LEED) standards as a green building yardstick, congratulations–you’re in good shape to attract that concerned majority. But your projects can stand out further from even the greenest competitors by getting a jump on green building’s next step–sustainable sites.To start with, there are currently 18 LEED points that are centered on the landscape. Including a LEED-accredited landscape architect on your team can increase the sustainability of a project in some very visible ways that are easy to highlight for investors and consumers. For instance, a landscape preserved in its pre-build state will require far less maintenance than an engineered one and can take advantage of existing shade trees for insulation. The landscape will look mature and harmonious and will save a project the cost of clearing and replanting.Heat island reduction is probably one of the best known green activities associated strictly with landscaping. Shade trees again have a powerful impact in this regard, cooling the ground and the air. But additional carbon dioxide removal can be achieved by increasing the number of trees and shrubs on a building site, or preserving those that are already there.Selecting green roofs, porous or light-colored pavements and sites near transportation and walkable amenities are other LEED-point clusters that a landscape professional can bring to your project. But there are many more sustainability tips and tricks that are about to come down the pike, which all of us in the housing business should be ready to digest.The fact is, in the USGBC’s urgency to release its LEED standards, issues concerning sites and landscapes were, for the most part, left out. But a powerful interdisciplinary coalition that includes the American Society of Landscape Architects (ASLA), the Lady Bird Johnson Wildflower Center and the United States Botanic Garden has come together to correct this oversight and formulate guidelines for creating sustainable sites. This alliance has the USGBC’s full endorsement, and the guidelines it generates will be incorporated into future iterations of LEED.Called the Sustainable Sites Initiative (www.sustainablesites.org), this interdisciplinary coalition is addressing land development and management practices for sites with buildings as well as for parks and other open spaces. Standards for sustainable sites are expected in spring 2009. A rating system, expected in spring 2011, will recognize performance in meeting these exterior standards.The partnership’s look at current research is yielding information about benefits not only to local environments and, potentially, global climate, but also to the people who live and work around greener landscapes–no surprise when you consider that LEED-qualified buildings have already been shown to reduce rates of respiratory disease, allergies and asthma among building residents, leading to lower absenteeism and higher productivity. Including land development standards in green building projects will increase these healthy-environment benefits. Positive social interaction is another benefit we can expect to find when landscapes are designed with well being in mind. For example, in a 2003 Journal of Arboriculture study of urban Chicago, the presence of tree and grass cover was tied to lower crime rates.Tremendous advantages to energy and resource conservation are linked to sustainable sites as well. In developing its recommended practices, the Sustainable Sites Initiative has rethought many of the traditional uses of water, soils, plants and materials in site design. The practices it recommends instead are intended to restore our ecosystem’s ability to regulate itself, reducing environmental damage in the process. Look at water. In the past, landscape design has treated rainwater as a waste product, using large drainage systems that dumped water rapidly into creeks and rivers, causing flooding and erosion and severely reducing the absorption of groundwater needed to keep soil healthy. This rapid runoff is often contaminated by the weed killers and fertilizers used to feed and maintain installed landscapes, which has downstream effects on wildlife and recreation. On the other side of the equation, high-quality municipal drinking water–in shorter supply all the time–is used to irrigate these human-altered gardens and lawns.How would Sustainable Sites address these issues of water waste and pollution? Instead of draining contaminated water away, landscape designers are encouraged to provide vegetated swales and filter strips to both clean and slow down water runoff. This water can then be harvested and used in place of municipal drinking water in irrigation systems, fountains and custodial applications. And water infiltration (to increase groundwater recharge, irrigate vegetation and reduce soil erosion) can be a built-in feature of landscape plans, by incorporating rain gardens and vegetated catchment areas to capture excess water.The recommendations briefly outlined here are taken from the Initiative’s “Preliminary Report on Standards and Guidelines,” released in November 2007. It is a strong start, and landscape architects will be watching its progress closely, as we have been encouraged to comment and contribute what we have learned in the field. Developers, builders and property owners who commit to sustainable site design will earn more LEED points, yes. But they will also increase asset values, tenant retention, and their reputation as green companies. When the green bar is raised higher, it will start from the ground up.Jo Ann Jarreau is a LEED AP credentialed landscape architect in the Houston area.