Sustainable Sites

By Andrew P. Borgese 

While there is much that could be written about how to design and construct green buildings, this article will take a step back in the timeline of a typical project and look at how the value of green architecture can be dramatically enhanced, and actually begins, with an understanding of how to identify, create and maintain sustainable sites upon which we choose to build.

Most of us, at some time or another have witnessed site clearing and earth moving during construction projects that often resulted in significant erosion problems because adequate environmental protection strategies were not employed. Similarly, many of us have seen how stormwater runoff can impact the quality of receiving waters and disrupt aquatic life. The inherent impacts of any kind of development will affect ecosystems in a variety of ways. Once we are aware of these impacts, we can take the necessary measures to protect our environment and preserve our natural resources. The development of greenfield sites, for instance, which are sites that are previously undeveloped, consumes land which is an increasingly valued asset particularly in urban settings and in communities where the remaining supply of undisturbed open areas is rapidly diminishing. Valuable agricultural land is being sacrificed for development purposes. Wildlife habitats are disturbed and sometimes completely destroyed as a result of poor development decisions.

The U.S. Green Building Council’s LEED (Leadership in Energy and Environmental Design) Rating System identifies several types of sites that should not be developed at all. These include [1] prime farmland areas; [2] previously undeveloped land within 5 feet of the 100 year flood elevation as defined by FEMA; [3] land specifically identified as habitat for any species on the Federal or State threatened or endangered list; [4] land within 100 feet of any wetlands as defined by U.S Code of Federal Regulations; [5] previously undeveloped land that is within 50 feet of a water body which supports, or could support fish, recreation or industrial use as per the Clean Water Act; [6] land which prior to acquisition was public parkland.

The general intent is to avoid development on inappropriate sites. The first principle of creating green and sustainable buildings is to locate them on appropriate sites that do not lead to the loss of prime farmland or wildlife habitat, and that do not adversely affect the surrounding ecosystems. Evaluation of the potential environmental disturbance of a particular site is often a good place to start. Wherever possible, development should be channeled away from environmentally sensitive areas and into previously developed areas. This type of approach has been successful in preventing sprawl and reducing habitat loss. This strategy also has inherent financial benefits by redirecting development to areas that may already have an established infrastructure of roadways, utility system distribution, stormwater management systems, wastewater management systems and other high cost development components. Previously developed areas that are within one-half mile of a residential neighborhood and within one-half mile of basic services such as grocery stores, banks, fire stations, libraries, post offices, restaurants and other similar facilities offer the added benefit of instant inclusion in an established and connected community environment. Site selection strategies can also be used to create opportunities for increasing the building’s efficiency and energy performance by locating the project in areas where natural ventilation and solar gains can be properly managed. These site characteristics combined with the availability of natural daylight can dramatically improve the indoor air quality of the building.

Once an appropriate building site has been selected there are different strategies that can be employed to conserve existing natural areas and restore damaged areas in order to provide habitat for the native wildlife and promote biodiversity. These can be accomplished by taking specific measures to limit the disturbance of the site during development activities and to plant a substantial portion of all previously damaged areas with native or adaptive vegetation. Other strategies involve integrating the site design and the building design in order to provide a high ratio of open space to development footprint to promote biodiversity. This can be accomplished by designing a building with a smaller footprint, reducing the amount of impervious or paved landscaping, constructing wetlands or naturally designed ponds, and providing vegetated roofs.

These site development strategies serve to protect and restore habitat and maximize open space, but they are also integral to the design of the stormwater collection and control systems. On a site designed with less impervious cover (less paved areas), there is greater capacity for on-site infiltration reducing the amount of stormwater runoff that can frequently overtax the municipal storm sewers and carry pollutants into neighboring streams, estuaries and oceans. By reducing impervious area, reliance on municipal or private on-site stormwater systems can be greatly reduced or even eliminated.

Other opportunities are sometimes available to reuse previously developed sites called brownfield sites. Brownfields are sites that are either contaminated or perceived to be contaminated. Although they are frequently located in urban areas where there is existing infrastructure, the stigma of a brownfield site can be a deterrent to potential buyers. While the public is often skeptical of new development, in the case of brownfields, communities and governments encourage redevelopment. Some of the benefits may include a greater availability of local labor, positive media coverage, appreciative customers, supportive community groups, and agreeable government agencies. Lower purchase prices offered as incentives to buyers may sometimes offset the costs incurred to remediate a brownfield site. In addition, using an existing infrastructure, including buildings and services, can be less expensive than starting from scratch and may cut the time it takes to go from acquisition to occupancy. Federal and state tax incentives are also available to help encourage brownfield redevelopment.

Before you consider embarking on a green building project, first make some informed and educated decisions about the site. Establish objectives that will limit the environmental impact of your development on local ecosystems and improve existing unsustainable design and construction practices. The selection of an appropriate building site can have a substantial effect on lowering the project cost while increasing building efficiencies. Appropriate site selection can offer tangible benefits to building occupants, reduce the long term operating costs and contribute to higher resale values.

© Copyright 2008 by The Enterprise - Upper Cape Cod News and Information 

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