When, in November, the U.S. Green Building Council took the stage at the annual Greenbuild International Conference in Philadelphia to unveil the release of LEED v4, the version instantly was compared to its predecessor LEED 2009.
The Irrigation Association (IA) chimed in on the conversation in the January issue of its IA Times e-newsletter, outlining the chief differences between the versions as they relate to water use and irrigation systems. They are as follows.
The key differences are in the point allocations. Projects that want to earn LEED certification must satisfy prerequisites within each of LEED’s credit categories in order to earn points—the number of points a project earns determines its level of LEED. In the water efficiency credit category, LEED v4 adds a mandatory requirement to reduce outdoor water use and three options to earn two points by reducing water use.
In LEED v4, projects can now use metering of irrigation systems to earn points. The latest version of LEED provides credit for projects installing submeters in two different areas where water is used. Landscape irrigation falls into one of these categories, with the installed meter monitoring water usage on at least 80 percent of the irrigated landscape.
In summary, LEED v4 offers the most points when projects do not install irrigation. This might be an option in regions that receive a fair amount of rainfall throughout the growing season, but it certainly isn’t an option in arid regions. These regions need irrigation to help establish plants and to assure that the landscape will be properly maintained to maximize the functional benefits it provides the building site.
Irrigation for future LEED projects will rely on water sources developed on-site, such as rainwater harvesting and reclaiming or reusing water that has been used previously for irrigation. LEED is changing the way projects are designed, built and maintained, which also changes the way projects approach landscape and irrigation.
Because LEED v4 was released a few months ago, the next few years will serve as a transition period in which projects move away from using LEED 2009. Until LEED 2009 is discontinued in 2015, projects are still able to determine which version they will follow to earn their LEED certification. Several IA members, including Netafim USA, Rain Bird Corp. and The Toro Co., have created online resources for projects following LEED 2009. These tools can be accessed on their respective websites and provide detailed information about how irrigation can be used to earn points for LEED certification.
