By Larry Myers

Utah Department of Transportation proves that highway projects with green goals can be delivered on schedule and under budget.

During the last fifty years, good environmental stewardship and sustainable development and living have increasingly pushed themselves from a fringe initiative into mainstream thought via public mandates and high-visibility reporting in mainstream news outlets. For decades, civil engineers have been involved in improving the environmental impact of construction projects. This is especially true in the design and construction of transportation projects.

It would appear difficult to fully account for and manage environmental impacts, particularly when most construction projects already face challenges such as limited funding availability, difficult collaboration across multiple stakeholder organizations, and the prospect of claims and litigation. Despite these significant challenges, the Utah Department of Transportation (UDOT) sets an aggressive goal to measure and mitigate environmental impact beyond the minimum required statutes that regulate UDOT design and construction projects.

UDOT is responsible for more than 6,000 miles of highways and bridges — 14 percent of the state’s total highway road system of 40,707 miles. This responsibility includes construction, repairs, maintenance, signage, and snow removal, as well as the Traffic Operations Center with live camera coverage for monitoring road conditions, accidents, and safety. UDOT’s primary mandate is to ensure the safe and effective transportation of persons and goods. However, it believes its responsibility for the well-being of Utah’s resident and visiting motorists includes more than just traffic safety. UDOT looks beyond just asphalt and concrete, and partners with local communities, transit agencies, environment advocates, and others to ensure that it provides the best overall product.

UDOT also takes into account the impact of construction projects on the surrounding community — both immediate impacts, such as traffic flow impingement, as well as long-term impacts, such as those affecting the environment. UDOT takes the initiative to evaluate and, where possible, mitigate the environmental impact of its construction projects. While examples of green design are rapidly increasing, the full-circle examples of green construction are still relatively few, particularly due to the difficulty of measuring the impact of construction processes. Despite little precedence, UDOT’s prevailing tenet is to do whatever it can to construct a road in the shortest time while minimizing the impact on the driving public.

Minimizing impact on Interstate-80
UDOT’s reconstruction of a heavily traveled, two-mile section of Interstate 80 (I-80) through the heart of Salt Lake City offered a good opportunity to implement innovative design and construction practices that significantly reduced the impact of the project on the community while meeting quality, time, and budget constraints.

On this project — one of the largest bridge reconstruction projects of its kind in the United States to date — UDOT used a construction management process that helped minimize the environmental impact of the reconstruction by reducing time of construction, construction pollution, and traffic congestion leading to automobile pollution. This contributed to quantifiably greener construction. UDOT reviewed various construction options using Oracle’s Primavera P6 Project Portfolio Management as a tool to assess the time impact of each option. The agency developed schedules that represented its standard construction method versus an Accelerated Bridge Construction (ABC) method that uses multiple prefabricated bridges — an innovative approach to bridge construction.

After the assessment, it was clear workers would be able to build the bridges faster and with less impact on traffic by leveraging ABC, so seven bridges were constructed offsite, then moved into place for final installation. This shaved one full year off of the construction schedule.

UDOT built half of the bridges for this project in one location, then moved and dropped them into place using a Self Propelled Modular Transport (SPMT) with several hundred wheels that is controlled by a single operator using a joystick. This lowered the emissions in the area by reducing the construction equipment and manpower needed to build and place the bridges.

In addition to the SPMT, UDOT used quick-setting concrete for approach slabs on adjacent bridge replacements, allowing workers to shut down the road for just a day and a half to pick up several old bridges, move them off to the side, and drop the new bridges into place. At each bridge location, the road was up and running again in about 36 hours, versus the four or more months of traffic congestion people would have experienced if workers had used more traditional construction methods. This process reduced traffic congestion and its associated increase in automobile emissions.

While some might see this offsite construction of bridges as a novelty, in Utah it is becoming the expectation for freeway bridge replacement. Constituents are extremely pleased with the reduced congestion and hundreds come to watch each “show” as workers move new bridges into place.

Measuring the results of ABC and smart project management
One of UDOT’s main goals was to reduce vehicle and construction equipment emissions during project construction. Since roadway congestion is one of the principal sources of increased emissions, a traffic plan was designed that minimized the impact of the project on traffic flow; this included using a movable barrier to increase the number of lanes open to traffic in the rush hour direction. In addition, operations that required significant lane closures were done at night or on weekends when traffic was the lightest. These methods reduced congestion during construction to near, or at times below, preconstruction levels.

On the construction side, the contractor was allowed great latitudes to find innovative solutions to reduce the effort it took to build the project while still meeting the contractual requirements. Oracle’s Primavera P6 was heavily relied on in this process. Weekly construction meetings were held where UDOT, the prime contractor, subcontractors, and other involved entities met to discuss construction progress. Primavera P6 was used to assess the impact of construction techniques and practices and to identify and resolve all problems to ensure that UDOT resolved issues quickly and effectively. These meetings resulted in the project being completed on time without any significant problems that hindered the work.

UDOT gained several advantages through its innovative approach on the I-80 reconstruction project. In terms of vehicle emission reduction, UDOT metrics show that contractor CO2 emissions were reduced by more than 20,000 tons and that the reduction of vehicle emissions from congestion due to construction activity was greater than 100,000 tons. In addition, it was able to reduce construction time from three years to two years, and reduce project impact costs to drivers through the project site by an estimated $10 million. Finally, pre-assembly of the bridges offsite ensured a safer and more efficient work environment that greatly reduced manpower and equipment requirements. In addition, public acceptance of the project was greatly improved because of UDOT’s efforts to minimize impacts related to the project.

Future use of project management to reduce costs and environmental impact
The successful use of ABC and project management as a construction management system has prompted UDOT to make continuous improvements to its construction practices. It continues to use Oracle’s Primavera P6 on all of its projects to ensure they are completed on time and within budget, and to measure the effectiveness of its construction programs.

In addition, UDOT has implemented some new practices that continue to show positive results. For example, it uses Price Plus Time bidding where contractors must bid construction time as one of the bid items. This is showing a marked decrease in the time contractors use to build projects. UDOT has also seen progressive examples where a contractor put in a conveyor belt system rather than bringing in trucks to move materials, which avoided crossing the highway, reduced carbon footprint, and almost completely eliminated highway delays.

At the end of the day, UDOT’s underlying goals are to continue to reduce the impact on motorists and the environment, reduce its own costs, improve highway construction, and deliver a better product to its constituents. By measuring and analyzing these factors, the agency believes that in just a few short years, it will be able to leverage best practices to be able to estimate closely how long, what means, and which methods are best to build just about anything, while managing all project constraints and emphasizing quality and efficiency.

Larry Myers, state project controls engineer, Utah Department of Transportation, has more than 30 years of experience in the engineering construction industry; half of which has been in the project controls arena. Some of his scheduling experience includes working as a project controls manager on several mega-projects for Fluor Engineers, plus helping establish the scheduling department for a large public utility in Northern California.