Water Conservation on Campus
In addition to water-conserving features in the newly-constructed Commons facilities, since 2007, Plant Operations has retrofitted over 500 bathroom fixtures producing annual savings of 10 million gallons of water – enough water to cover a football field 30 feet deep in water or fill 333,000 bathtubs – and $67,000 on Vanderbilt’s main campus. Plant Operations plans to make all non-residential urinals waterfree by 2013.
Low Flow, No Touch Faucets
Low flow, no touch faucets are sensor-operated, turning on when hands are present and off when hands move away. This helps limit water flow and prohibits the spread of germs from touching the faucet handle. Low flow faucets use an aerator to mix air in the water, reducing the flow necessary to achieve the same wetness by about two-thirds.
Low Flow Toilets
Toilets are often the single largest users of water in many facilities. One flush of each standard toilet uses 3.5-5.5 gallons of water. Low flow toilets require only 1.2-1.6 gallons per flush. Today’s low-flow toilets are designed to operate very well under low-flow conditions, eliminating the need to flush twice.
Waterfree urinals do not flush, so they use no water. An internal trap is filled with a liquid chemical lighter than urine. The urine sinks below it and is directed down the drain by gravity, eliminating odor from entering the restroom. Each waterfree urinal can save up to 40,000 gallons of water each year over a traditional urinal.
Dual-flush toilets use less water to flush liquid waste (0.8 gallons per flush) and more for solid waste (1.3-1.6 gallons per flush). They are designed with a larger trap (the opening in the bottom) and don’t keep much water in the bowl like traditional toilets.
Utility Tunnel Water Capture
Non-potable groundwater is collected from the utility tunnels and pumped to the cooling towers at the on-campus cogeneration power plant and used for irrigation on Vanderbilt’s athletic fields. By capturing this water and redirecting it, Vanderbilt is reducing water purchases from Metro Water and sewer by 50 million gallons a year.