One of the key questions on transportation planners' minds across America today is "How can we make our transportation more sustainable?"
The engineers, analysts, planners, architects, and policy makers gathered at the first Green Streets & Highways conference in Denver this week set themselves the important task of trying to answer that question with regard to America's roadways.
The conference was hosted in part by our Federal Highway Administration, and Administrator Victor Mendez set the tone with his keynote address.
Administrator Mendez and I are proud of DOT's representation at this week's conference. FHWA professionals numbered among the presenters and technical staff, and quite a few FHWA Division Administrators were in attendance. We believe it’s the largest showing by FHWA at any event of this kind.
So, can American roads be built to respect their surroundings and help sustain the planet? Administrator Mendez's answer was a confident "Yes."
As Administrator Mendez said:
"This means not only building roads to enhance safety, increase mobility, and enable the economy--but also so they have less environmental impact and use fewer resources to build and maintain. We're encouraging planners and engineers to explore the use of new materials that help us deliver projects so they’re more sensitive to the environment. We need to make greater use of recycled materials, materials that absorb sound and smog, and materials that make roads more durable and require less maintenance."
Some of those materials and technologies are already in development or use.
One material Administrator Mendez discussed is Calera, which allows road builders to make cement products and aggregates from sea water.
Another is warm mix asphalt. With this approach, asphalt can be mixed and put on the road at temperatures 30 to 120 degrees lower than the traditional hot mix, cutting fuel consumption by 20 percent.
Adaptive signal control adjusts traffic lights to real-time traffic conditions, keeping traffic moving and reducing emissions from congestion.
Using prefabricated bridge elements--where parts of a bridge are built off-site, then assembled on-site--reduces the traffic tie-ups and congestion that result when roads have to be closed for conventional bridge construction.
And one way to encourage the transportation community to think bout environmental issues is to have a tool for measuring whether we’re creating sustainable highways. Well, thanks to the leadership of Associate Federal Highway Administrator Gloria Shepherd, we now have such a tool. INVEST is a voluntary, web-based tool for measuring sustainability over the entire life of a project, from planning through design, delivery and operation.
Now, these are just a handful of new approaches to designing, building, and operating America's valuable roadways. But, as Administrator Mendez told this week's Green Streets & Highways Conference, we won't stop there.