Water / Energy Nexus Study

Saving water also saves energy and vice versa...

A Water / Energy Nexus Study is a Neutrality goal in the Cornell Climate Action Plan (CAP).

Complete a water/energy nexus study for the Cornell campus and implement comprehensive strategies to monitor usage, conserve water, and reduce energy associated with treating potable and waste water.

Goal: Quantify energy use associated with the campus water delivery system, and implement measures to optimize the system and conserve both energy and water.

The source of Cornell’s water is the 125-square mile Fall Creek drainage area. Cornell’s Water Filtration Plant provides a population of about 34,000, including the campus community and residents of the adjacent Forest Home and Cornell Heights neighborhoods, with safe and reliable drinking water. In 2012, the plant produced 507,000,000 gallons of potable water: approximately 9% of this water was used to generate energy for campus, while 91% of the total supplied campus potable water and agricultural needs.

Water and energy are inherently linked, intersecting on both the supply side and the end use side. This intersection is commonly called the “water/ energy nexus.” Efficiency programs that save water will also save energy and vice-versa. To more precisely quantify the energy associated with Cornell’s water system, the Water Team is proposing a water/energy nexus study for the Ithaca campus. This study will quantify energy use associated with the current water delivery system as a basis for prioritizing and implementing infrastructure upgrades, such as pump replacements. The study will also provide a basis for implementing water conservation measures on campus, by linking these measures to reductions in energy use.

A preliminary analysis conducted in 2012 showed that approximately 4% of campus energy is used to treat and pump campus potable water, and 9% of campus water is used to generate energy. The next phase of the study will assess how much energy is used to treat campus wastewater at the Ithaca Area Wastewater Treatment Plant, and may also attempt to quantify the volume of water used to extract the natural gas used to generate campus electricity.

Approximately 15-20% of the water Cornell produces is currently unaccounted for. Metering all of the water produced would stabilize water rates and share costs equally among all customers. Utilities staff will continue to search for unmetered locations and install water meters as needed. In the longer term, water usage will also be added to the Cornell University Building Dashboard, so that colleges and units can track their usage and save money by adjusting their consumption.

Next Steps

  • Complete the water/energy nexus study, including a cost-benefit analysis, evaluate the study recommendations, and present findings to campus Utilities staff.
  • Find un-metered water on campus. Install sub meters at strategic locations to account for all water used on campus and stabilize water rates for all customers, including Town of Ithaca and City of Ithaca customers.
  • Add water usage to the Cornell University Building Dashboard.
  • Include water conservation in the college engagement campaign, Think Big, Live Green.


Collaborate on joint water and energy utility programs to maximize savings and share tracking, metering, and data evaluation responsibilities.