Focus on Green Construction

March/April 2009

On the Road

More education, industry-wide acceptance are keys to the further greening of highway construction

By Jennifer Seward

While reconstructing California’s Interstate 5, Flatiron is making about 300,000 tons of aggregate by crushing up old materials from I-5 and other roadways in the area. (Photo Courtesy Flatiron)

While office buildings, hospitals and schools may have the U.S. Green Building Council’s Leadership in Environmental and Energy Design [LEED] guidelines to drive sustainable construction practices, the horizontal side of the industry is working at a grassroots level to raise green awareness.

“The highway industry has historically thought of environmental awareness as simply preventing pollution,” says Geoff Boraston, director of environmental affairs for Granite Construction, a California-based highway contractor with offices around the country and a member of several different AGC chapters.

But Boraston says times have changed, and contractors have started to recognize that green is much more than that, as fuel conservation and the protection of natural resources now become priorities.

While there is no special selection process or certification program for green highway contractors, the Green Highway Partnership, formed in 2005 by the Federal Highway Administration (FHWA) and the U.S. Environmental Protection Agency, is bringing transportation and environmental groups together to talk about practices that can make highway construction greener. GHP partners include a range of federal and state transportation and regulatory agencies, as well as contractors, trade associations and other industry-related groups.

“The equipment, materials and technology [for green highway construction] is available,” says Jason Harrington, FHWA recycling technology engineer. “But this information is scattered.”

GHP, a voluntary public/private initiative, is initially focusing its efforts on the mid-Atlantic region. The initiative’s Website says it seeks to incorporate environmental streamlining and stewardship into all aspects of the highway lifecycle through concepts such as integrated planning, regulatory flexibility and market-based rewards.

One of the industry’s hurdles is where to go for the most comprehensive information: specifications, performance, design-guidance or environmental issues. It takes money, time and direction to put it all together, Harrington says.

Although GHP was never intended to be a certification program, it is helping to define best practices through workshops and educational programs on topics related to building highways.

For now, even without industry-driven standards, recycling is one aspect of highway construction that has not only become commonplace but is considered by many contractors as the key to staying competitive. “If a contractor isn’t even recycling asphalt, something is really wrong,” Harrington says.

Bob Lanham, vice president of Houston’s William Bros. Construction Co. Inc. (AGC of Texas Highway, Heavy, Utilities & Industrial Branch member), says his firm recycles about a half-million tons of concrete and asphalt each year, “and we’ve been doing it since 1990.”

Lanham says the story is not being told about how much recycling actually goes on in the highway industry. For instance, most of the steel beams and reinforced steel used in Williams Bros.’ projects are recycled scrap. Even the traffic barrels are made from recycled plastic.

“The nature of our industry is to just do it, regardless of specifications, because it’s economically and environmentally a good thing,” Lanham says.

According to the National Asphalt Pavement Association, about 100 million tons of asphalt pavement is reclaimed every year, and more than 95% of the reclaimed material is reused or recycled.

“Reusing and recycling asphalt pavement contributes over time to decreasing energy consumption, lowering oil demand and reducing the carbon footprint,” says Jay Hansen, NAPA’s vice president of government affairs.

NAPA estimates that 50,000 “green-collar” American jobs are created or sustained annually as a result of the industry’s recycling, and that number should increase with help from the stimulus package.

New Ways of Working

Firms like Longmont, Colo.-based Flatiron Construction Corp. (Colorado Contractors Association Inc. member) take asphalt recycling one step further by using a portable crusher to make aggregate base material onsite. While reconstructing sections of California’s Interstate 5, Flatiron is making about 300,000 tons of aggregate by crushing up old materials from I-5 and other roadways in the area. Interstate 5, one of the state’s original freeways, stretches from Mexico to Canada.

Rick Finken, a Flatiron project manager, says this type of recycling is imperative for the firm to keep its costs down, and that many companies are now cropping up in Southern California to provide portable crushing services.

Granite Construction performed a warm-mix paving demonstration for the city of Indio, Calif. Public agency representatives were invited to observe the project, done with recycled asphalt. (Photo Courtesy Granite Construction)

“Twenty years ago, demolished material was hauled to the landfill; now it’s piled up, fed into the crusher and turned into aggregate onsite, saving the cost of hauling it away and bringing in new material from a [distant] quarry,” Finken says.

Flatiron owns its own crushing equipment. Two main units, conveyors, a control tower and generator are loaded on five semi-trucks and moved from job to job.

Finken says owners used to require 100% new material, but are now relaxing their specifications to allow for more recycled materials and green alternatives.

Arkansas’ Weaver-Bailey Contractors (Arkansas Chapter-AGC member) has recycled 100% of the concrete paving on its projects since 2000.

Don Weaver, the firm’s vice president, says recycling gives contractors an advantage in the bid process, helping them lower the costs of materials and hauling and, ultimately, reducing traffic disruptions for the public.

“Just by adding lanes, we’re being green,” says Weaver, citing studies that show the pollution level goes down when traffic is flowing and fewer cars are idling.

When Weaver-Bailey constructed the $63-million Interstate 40 project, the largest job in Arkansas history, “hardly anything went into the landfills,” Weaver adds. Completed in 2006, the three-year project expanded the highway from four to six lanes and built three new overpasses.

Not One Size Fits All

Lenny Boteilho, a senior manager with Ames Construction Inc., Salt Lake City, (Utah Chapter-AGC member), says most of the bigger contractors are figuring out how to make green practices a routine part of their business. Ames is currently widening a highway through a forest in Wyoming, and the trees it’s removing are being turned into mulch for reuse.

“In regions we bid in, everyone is using the same technical green approaches,” Boteilho says. “Four or five years ago, no one would have considered [these practices], yet today many consider recycle and reuse standard protocol.”

Recycling is only one part of the picture. Before highway contractors can jump on the green bandwagon, the industry must try to understand and embrace what green means for this sector.

Lanham says that there are a lot of discussions about how to make highway construction greener, but there’s still no widespread acceptance of green construction practices from the owners’ side.

Lanham adds it has been a challenge for AGC to help the engineering community, the owners and specifiers “come to grips with [the fact that using] recycled materials does not mean providing a substandard project.

“Education is key and owners must become smart about using unlimited resources,” he says, insisting that his peers will respond to green specifications if owners ask for or permit them. “Contractors are creative. Give us the opportunity, and we’ll figure out ways to handle it. We have to be smart about this. It’s not a snap-your-fingers, one-size-fits-all answer.”

Building Green Bridges Colorado-based Flatiron Construction Corp. is engineering ways to build bridges in more environmentally sensitive ways. While constructing the Washington bypass in North Carolina, Flatiron’s inhouse engineers designed a process that eliminates the need for temporary access trusses. It creates a permanent structure that ultimately reduces the construction impact when it is adjacent to a wetland. Flatiron Construction’s in-house engineers designed a process that eliminates the need for temporary access trusses by creating a permanent structure that ultimately reduces construction impact when work is being done adjacent to a wetland area. (Photo Courtesy Adriano Fontana) The new 6.8-mile bypass around Washington and Chocowinity, N.C., includes construction of a 3-mile bridge over the Pamlico-Tar River, where Flatiron is utilizing its new patent-pending variation of the top-down construction technique. This span-by-span construction method uses the newly constructed permanent structure for personnel access and material deliveries. The process consists of self-contained gantries that can perform all tasks associated with the bridge construction, including driving the precast piles, building the bent caps, erecting the 120-ft-long precast girders and pouring the deck. All of these operations will be performed without the use of temporary access trestles, thus significantly reducing environmental disturbances. Elie Homsi, Flatiron’s vice president of engineering services, helped develop the award-winning technique and says the system is meeting and exceeding the firm’s expectations. Homsi was recently honored with an Engineering News-Record Top 25 Newsmaker award for helping to develop the system.