One way to look at water in the context of reducing green house gas (GHG) emissions is to account for the fact that certain energy efficiency improvements reduce water use. In other words, the economic value of energy efficiency is often greater than just the economic value of the energy saved. For example, energy efficiency improvements that reduce cooling loads will save a proportional amount of cooling tower water. When cooling towers use less water, they require proportionately fewer chemicals, maintenance, etc. Therefore, a cooling efficiency improvement will result in savings in the cost of energy, the cost to purchase water, the cost to discharge water to the sanitary sewer, the cost of cooling tower chemicals, and the cost of cooling tower maintenance. Economic justification is easier when all of these cost savings are captured. The Illinois Sustainable Technology Center has performed true cost of water accounting for Ford and Caterpillar, and the results have shown that the actual cost to use water can be 5 to 20 times greater than the cost of the water alone.

Campus has begun to utilize efficient water fixtures, including low-flow aerators for faucets, dual-flush and high efficiency toilets, high-performance low-flow showerheads, and pint urinals. These fixtures will continue to be utilized in new buildings and retrofits, and newer technologies to improve upon these efficiencies will be researched and harnessed. Non-potable sources of water will also be utilized when appropriate, including untreated raw water, sump pump discharge, cooling tower wastewater, stormwater, and graywater. The University has a raw water system across campus that has yet to be activated. This would allow campus to purchase lower cost, non-treated raw water from the water company. The Business Instructional Facility is already plumbed in a way that would allow for raw water to be used for toilet and urinal flushing when available. The BIF greywater pipe system project was developed to allow for greywater usage and real-time water meters are pilot tested in some campus buildings.