How green is a parking lot? New efforts to test infrastructure

Apr. 12, 2012
How green is a parking lot? New efforts to test infrastructure
David J. Unger | Medill News Service

WASHINGTON — A growing number of civil engineers, landscape architects and urban planners are making a case for not just repairing but also for greening the structural underbelly we rely on to drink our water, cross our rivers and park our cars.

"The question was frequently, 'Who will be the LEED-certified engineer on that runway project (or) that water treatment facility?'" said Pat Natale, executive director of the American Society of Civil Engineers, referring to the coveted Leadership in Energy and Environmental Design certification from the U.S. Green Building Council.

Using LEED guidelines for runways, roads, water plants and other infrastructure "didn't fit," Natale said. "You could twist it a little bit, but it didn't fit."

While LEED has raised the profile of "greening" buildings, infrastructure — the spaces on and through which we live — doesn't always conjure up images of eco-friendly design.

"We have no connection to our infrastructure, it magically happens," said Bill Worthen, the American Institute of Architects' resource architect for sustainability. "We have no understanding or placement of value on all the stuff that's under our feet that keep us functional, and it's all starting to fail."

The first step in improving the performance of just about anything is to measure it.

"That infrastructure platform is begging for a rating tool that will balance development and environmental concerns and return on investment," said David Raymond, president and CEO of the American Council of Engineering Companies.

Last week, the Institute for Sustainable Infrastructure unveiled Envision, a new rating system designed to provide third-party certification for green infrastructure.

Envision aims to be to bridges, roads and parking lots what LEED is to homes, businesses and offices, its creators say. Using a point system to cover 60 criteria across five categories, Envision gives engineers, infrastructure owners, policymakers and others a framework for evaluating the environmental impact of infrastructure projects.

"If we can't define sustainability, we can't measure it," said Paul Zofnass, founder of the Zofnass Program for Sustainable Infrastructure at the Harvard Graduate School of Design, one of the collaborators behind Envision. "If we can't measure it, we can't assess it. If we can't assess it, we can't improve it."

The American Council of Engineering Companies, the American Public Works Association and the American Society of Civil Engineers are also backing the new assessment tool.

Envision is not the first or only rating system for sustainable infrastructure. Sector-specific guidelines exist for roads and ports. The Sustainable Sites Initiative is a similar tool used for sustainable land design, construction and maintenance — many of whose principles are incorporated in Envision.

The Green Highways Program, a partnership between the Environmental Protection Agency and the Federal Highway Administration, uses a green roads rating standard that aims to identify sustainable new or rehabilitated roads.

What, then, is a green road? What could you possibly do to make a stretch of asphalt — or any type of infrastructure — any more or less green?

For starters, experts say, you could use a lighter shade of pavement. Dark pavement has a tendency to absorb light, meaning it takes more electricity to keep streets and parking lots adequately lit at night. You might reduce the number of lanes dedicated for cars, install bike lanes and widen the sidewalks, thereby promoting walking and biking.

Even sidewalks can benefit from sustainable upgrades, including the use of pervious concrete, which allows rainwater to trickle down beneath it, managing storm water runoff while better watering trees planted along a streetscape.

Cities are catching on to the benefits.

In November 2010, the District of Columbia Department of Transportation broke ground on the Nannie Helen Burroughs Avenue Great Streets Project, which implements pervious concrete, traffic-calming measures and other components of green street design. The project has an estimated completion date of May 29, said Jasmy Methipara, office engineer for the project.

Boston's Complete Streets approach calls for streetscape designs that incorporate permeable paving materials and natural alternatives to unsightly storm-water runoff systems.

In Chicago, even the streetlights are going green — in spirit if not in color. The city's department of transportation plans to install more than 1,200 new energy-efficient streetlights across Chicago in 2012.

"We're really starting to look at infrastructure, and the way that we develop it is quite different," said Neil Weinstein, executive director of the Low Impact Development Center, a Beltsville, Md.-based nonprofit organization that works on natural resource protection issues.

Instead of thinking of a road as a simple stretch of asphalt, Weinstein says engineers and designers are concentrating on infrastructure's "triple bottom line" — a cost-benefit analysis that takes into account not only a project's economic impact, but also its social and environmental effects.

Engineers and architects say the changes cannot come quickly enough.

"This need for more and greater infrastructure, in our view, is not going to go away," said Zofnass. "There has never been a government that has survived if they could not provide their society, their people, their civilization with adequate and improved infrastructure."

(The Medill News Service is a Washington program of the Medill School of Journalism at Northwestern University.)