When the Metropolitan Nashville Airport Authority took on the challenge of building a new airport cooling system, sustainability was the goal.

“There’s a real misconception that sustainability costs more,” said Christine Vitt, vice president of strategic planning and sustainability for the Airport Authority. “It just makes economic sense, and it’s part of our long term thinking and planning,” she said.

For help they turned to Envision, a resource provided by the Institute for Sustainable Infrastructure (ISI). Envision consists of dozens of broad-ranging criteria that help people make better decisions at each step of a project. It provides a framework for evaluating and rating a project’s community, environmental and economic benefits. Many public agencies are using Envision for project assessments and including Envision details in requests for qualifications (RFQs) and requests for proposals (RFPs).

The end result: The Airport Authority turned an old rock quarry lake into a tremendous resource.

Its Water Source Geothermal project created the largest lake plate cooling system in North America. Stainless steel plates are positioned 50 feet down into the quarry lake, where the temperature is a constant 50 degrees. A piping system circulates the water throughout the airport terminal, leading to a cool $430,000 savings per year in utility costs.

Just as the Leadership in Energy and Environmental Design (LEED®) ratings system from the United States Green Building Council is used to certify sustainable buildings, ISI recognizes sustainable infrastructure projects ranging from power plants to wastewater facilities, even hydroponic farms. The Water Source Geothermal project just earned the Envision Silver Award.

A recent platinum award winner is the Holland Energy Park in Holland, Michigan, completed in 2016. Combining natural gas with renewable energy, the power plant provides a 50 percent reduction in carbon emissions and nearly eliminates particle pollutants. This was the first power plant to win an Envision award.

ISI may be just the cavalry needed to help companies and municipalities design, build and retrofit hundreds of projects, from roads to bridges to ports and dams. With talk of a trillion federal dollars slated for upgrading America’s infrastructure, the time is right to embrace sustainability.

“We have a tremendous opportunity, a once in history opportunity, to really shape the future through infrastructure,” said Melissa Peneycad, director of sustainable projects for ISI. “We can have positive community impacts if done appropriately, or we can saddle future generations with unsustainable decisions. Certainly we would encourage all projects to use the Envision system.”  

Peneycad said the system evaluates projects holistically. Beyond considering upfront costs, design and construction teams are encouraged to incorporate long-term operational costs — and future needs — into their thinking.

“So, for example, should a wastewater treatment facility be built to meet current demands? Or should it take into account future demands to save from building a separate facility in the future? To design it with the flexibility to expand can lead to cost savings,” said Peneycad. A project may also be designed and built to more resilient standards in order to cope with the unknowns of future climate conditions.

Active engagement in the sustainability mission on the part of the contractor is key.

“In my experience, more contractors than you might think really welcome opportunity to be engaged in the process,” said Peneycad. “Some of the most successful projects got contractors involved early, rather than being told later, ‘Thou must do this!’. They have a huge opportunity to contribute. They know the challenges they might face, things the design team might not have thought about.”

In Nashville, Vitt said there’s been a real change in culture for the engineers and construction teams involved in weaving sustainability criteria into engineering projects. She added, “Adopting new policies is fun after you get into it. It gets people thinking differently.”