LEED-EB And Water Efficiency
OTHER PARTS OF THIS ARTICLEPt. 1: LEED-EB Requires Energy Efficiency MeasuresPt. 2: This PagePt. 3: Creating Sustainable Purchasing PoliciesPt. 4: Recycling Your Way To LEED-EBPt. 5: IAQ And LEED-EB
Studies show that many of the most plentiful sources of fresh water are diminishing. According to EPA, at least 36 states are anticipating local, regional or statewide water shortages by 2013.
If it’s not already known, facility executives should calculate their facilities’ water use, because the total is often more than expected. According to USGBC’s Existing Buildings: Operations & Maintenance Reference Guide, 2008, a typical 100,000-square-foot office building in the U.S. can use more than 3 million gallons of water per year.
In most buildings, there are three main areas of water use: domestic water, irrigation, and process loads such as kitchen equipment and mechanical equipment. For determining domestic water use, LEED–EB includes a water use baseline calculation that will allow facility executives to see how plumbing-fixture water use compares to what USGBC has determined to be the standard for green building.
|Water closets||1.6 gallons per flush (gpf)
|Urinals||1.0 gallons per flush (gpf)
|Lavatory faucets||2.0 gallons per minute (gpm)
|Kitchen sinks||2.2 gallons per minute (gpm)
|Shower||2.5 gallons per minute (gpm)
If aerators rated at 0.5 gpm were added to lavatory faucets, water-use would fall to 17 percent below baseline. This inexpensive upgrade drastically reduces water use.
Given that the U.S. Department of Energy estimates restroom plumbing fixtures account for approximately 60 percent of total water use in office and administrative buildings, upgrading plumbing fixtures can have a huge impact. Using low-flow fixtures, low-flow toilets, and implementing water-saving strategies in this example facility could save more than one million gallons of water per year.