Three-Season Project

Story by Gene Storm | September 28, 2010

A five-mile section of Alaska's Glenn Highway is getting a major makeover in a $26.2-million project that will span almost three construction seasons. The project from mile 92 to mile 97 northeast of Anchorage includes realignment and reconstruction of the road, a new bridge over Hicks Creek, the replacement of several culverts, and moving massive amounts of dirt and rock in the rugged back country that defines much of the highway's route.

Anchorage-based Alaska Interstate Construction started work on the project in early April 2007 and anticipates laying the final lift of asphalt in June 2009. In achieving project completion, AIC crews and equipment will move an estimated 1.8 million cubic meters of material. Of that, 1.2 million cubic meters will be rock blasted and excavated along the road's new alignment.

The Glenn serves as a connection to the Richardson Highway and the Alaska Highway beyond, making it a major link to Anchorage, particularly during the busy visitor season. For AIC, controlling the traffic through the construction zone is a significant challenge, according to Project Manager Brent Cleaves.

"As for any job, traffic has been a challenge. We have had a road closure from midnight to 6 a.m. five days a week that has helped with production. When the road is open a pilot car ferries traffic the length of the job," said Cleaves.

Weather conditions, often challenging, have generally been a plus for AIC.

"This season for the most part has been a good year for building a road; we had a late start on summer, but the weather is working out to be cooperative," noted Cleaves. That was especially true at the end of the construction season as work continued late into October with warmer than normal temperatures and only traces of snow over the project area.

Surprise Soil Conditions

Uncertainty can present its own set of challenges, and that has proven to be the case for AIC on a portion of this project. Geotechnical data on a steep embankment at the center of the project did not represent the conditions that AIC found when they began work in the area.

"The conditions we found while pioneering access to the top of the cut early in the season were not what the original design was based upon," said Cleaves. "The soil and overburden depths we encountered at the top of the rock cut were much greater than expected," he added.

"This finding has had a large impact on the productivity of the project not only because it is located at the center of the job, but also because it accounts for a large amount of material that is to be used in fill areas toward beginning of the project. It also creates inefficiencies and added costs that have not fully been tallied," Cleaves concluded.

While the Alaska Department of Transportation and Public Facilities works with consultants in gathering further data for a redesign of that portion of the project, AIC worked in a section of the cut that had less overburden. That allowed the overburden to be laid back at a safe slope above the rock face. It is anticipated that the new design and a price tag for the additional work will be completed in time for the beginning of the 2008 construction season.

Constant Motion

While work on the cut at the center of project proceeded at a tentative pace, it was moving quickly on the rest of the project. AIC has an impressive fleet of heavy equipment that is in constant motion throughout the project. The equipment inventory includes three Caterpillar D10 dozers, a D8 and two D6 dozers; a fleet of Cat excavators including a 385, 365, 330, and a 315; six Volvo A35 rock trucks; four Terex TA40 rock trucks, which includes two that have been converted into water wagons; seven Euclid B70 haul units; three Terex S24 scrapers; two Cat 16G graders; and a fleet of support equipment to keep everything up and moving. The drilling and blasting operations are supported by five Ingersoll Rand 590 drills and an Atlas Copco DM-30.

Some 4,000 gallons of diesel fuel per day keeps the equipment fleet on the move. An equipment service area and fuel yard serves a focal point for servicing the fleet. Tanker trucks make deliveries twice weekly, off-loading to the on-site fuel tank.

"Being out of town always adds issues with getting materials, but we have been lucky with the support from our suppliers and our in-house expediting team," Cleaves said.

The new road alignment will include the new 109.5-meter bridge over Hicks Creek. The bridge will be anchored by two piers within the floodplain and two pile-supported abutments that will tie the structure together. AIC was working toward having the bridge girders in place by the end of the 2007 construction season.

Project management and the coordination of the more than 100 craft employees are taking place out of office quarters more substantial than the typical construction site re-locatable trailer. AIC struck a deal with the owners of Nova River Runners to lease a two-story frame building that served as Nova's headquarters. At project's end, Nova will return to a headquarters building made more accessible by the new road alignment.

Other property, including the Hicks Creek Lodge, was acquired by the state to accommodate the highway realignment. A historic building that was part of the lodge was donated for restoration at another location along the highway.

The remote location of the project means that small AIC cluster communities have taken shape at lodges and RV parks that dot highway near the construction zone. These locations provide a home away from home for workers who have logged long hours spread over two shifts.

When completed, another section of the sometimes steep and serpentine scenic Glenn Highway will provide a safer trip for motorists.