Potable water refers to water that is safe to drink, a scarce commodity in developing regions and an increasingly precious resource worldwide. On campus, we are implementing infrastructure to conserve potable water used for non-drinking purposes (e.g., sinks, faucets, toilet fixtures, plumbing, cooling, and irrigation). In FY19, campus used 823,049 kgal of water (Figure 17). 

As of FY19, we have reduced potable water consumption by 37% from the FY08 baseline (Figure 18).[1] To reduce consumption by another 8% by FY24, we will focus on the two largest sources of excess water usage: campus buildings and agricultural irrigation.

Figure 17: Total Potable Water Used on Campus

Figure 18: Percent Reduction in Potable Water Consumption

Water consumption in campus buildings

Restrooms in campus facilities are a common source of water inefficiency, as many plumbing fixtures are not up-to-date with current conservation technology. Previous sustainability projects have addressed this by updating campus facilities with low-flow fixtures. As of FY19, there are approximately 1,100 lavatories that must be converted to low-flow, about 500 urinals that use one gallon per flush (GPF) rather than 0.5 GPF or 0.125 GPF, and approximately 1,100 toilets that use three or more GPF. The most efficient flush rates are as low as one GPF in newer campus facilities. Though retrofitting existing fixtures is difficult, we will continuously research water reuse techniques and require low-flow fixtures for all new construction. The Building Maintenance team at F&S is compiling an inventory of buildings that lack low-flow fixtures in restrooms; upon its completion, we will identify the buildings with the most fixtures to retrofit and seek funding to implement these improvements.

Housing has contributed greatly to water use reduction in dining facilities by transitioning to trayless dining. Simply removing trays in dining halls saves 516 gallons of water per day and 110,940 gallons annually. Their recent adoption of the Grind2Energy system will also contribute to a notable reduction in water consumption. 

In research labs, it is not uncommon for equipment to use a “once-through” cooling system — as its name implies, the (often potable) water used for cooling has a brief lifespan, passing through the machines just once before being discharged as wastewater. This process is needlessly wasteful. After identifying which equipment relies on once-through cooling systems, we will explore ways that these processes can be redesigned to incorporate more sustainable practices. 

In addition to upgrading our facilities, we will communicate water conservation best practices to building occupants: students, staff, faculty members, and facilities staff. Communicating water consumption will bring awareness to the rate and volume at which campus buildings consume water, and will encourage individuals to make decisions supportive of the iCAP objectives. 

Agricultural water usage

Agricultural research is central to the university’s mission. Even though a small fraction of the 3,300 acres devoted to crop cultivation requires irrigation, water use volumes are staggering. For example, a 40-acre field irrigated with 10 inches of water over the course of a year will require over 10 million gallons annually. To achieve a 45% potable water use reduction, irrigated university-owned land must be transitioned from municipal water sources to reclaimed water sources or wells. 

[1]  https://bit.ly/2Xlnfcz