By John Schinter, Executive Director of Energy, AT&T, and Gwen Ruta, Vice President of Corporate Partnerships, Environmental Defense Fund

We live indoors, we work indoors, we shop indoors, we even often play sports indoors.  With so much of the modern American economy taking place indoors, and population centers shifting to warmer regions, the environmental and economic impact of building cooling systems is on the rise. We often hear about the energy needed to power and cool this sprawling infrastructure.

But there’s another crucial dimension that is only just starting to surface: water.

As water becomes a more expensive, and sometimes contentious, commodity in many regions like the drought-stricken southwest, managing thirsty commercial buildings is going to become an increasingly important challenge for building owners.

In most large commercial and industrial buildings, tens of thousands of gallons of water flow through a big apparatus called a cooling tower (about the size of a two-car garage, they’re usually on the roof), where it evaporates out the top.

The U.S. Geological Survey estimates that commercial, residential and industrial buildings use approximately 47 billion gallons of water each day. And the EPA found that a typical office building uses more than 25 percent of its water supply for cooling towers.

Now, with all that water adding up, leading-edge companies are starting to rethink these systems. Environmental Defense Fund (EDF) is teaming with information and communication technology (ICT) giant AT&T, which operates thousands of facilities across the country. Together, we’re looking to develop operational improvements and best practices that can cut water, chemical and energy use in these cooling systems and improve overall building efficiency.

AT&T has calculated its water footprint, discovering that just 120 of its facilities accounted for nearly half the company’s 3.4 billion gallons of water used in 2010. The company rolled out its Water Scorecard to pinpoint potential water-savings opportunities and trained facility managers in an effort to increase awareness and understanding of water usage. It was clear that cooling towers represented an opportunity to improve efficiency.

Together, EDF and AT&T will build on those learnings. We will evaluate facilities and operations for efficiencies, and explore more creative ways to drive water and cost savings. We will look at the whole cooling process and pursue ways to eliminate cooling tower water use by utilizing cool, outdoor air to cool indoor space where feasible.

Quick calculations suggest that improving operations in the cooling towers at AT&T's largest facilities could save millions of gallons of water per year. Adopted on a broad scale, these solutions could save billions of gallons of water annually.

For example, if operational improvements were adopted across all existing commercial office buildings and manufacturing facilities in the Dallas/Fort Worth area in Texas, the water savings could be over 12 billion gallons per year. That’s equal to the water use of nearly 500,000 homes or approximately 13 percent of the water use in the region. Together, EDF and AT&T  have agreed to pilot best management practices and new technology at target facilities, and we plan to share our progress as we move forward with the project. Stay tuned for more updates as we uncover opportunities to improve efficiencies at the water/energy nexus.