The project’s goal was to increase access across the island for recreational and subsistence activities.
Kiewit Infrastructure West Co. was selected through a best value procurement process to serve as the Construction Manager/General Contractor (CM/GC) for the Kake Access Road project, located in the Tongass National Forest on Kupreanof Island in Southeast Alaska. This challenging project was completed one year ahead of schedule as a result of the team’s successful collaboration with the client on the region’s first CM/GC project.
The project scope included building a road that would provide year-round surface transportation access between the community of Kake and a new boat launch on the eastern shore of the island, providing public access to lands along the route, as well as creating an additional access point to navigable waters on Frederick Sound.
Clint Lane, the project manager for Kiewit, said he and his team mapped out a Plan B and Plan C for each operation because of the remote location and rough terrain.
“When we encountered alignment changes or design changes on one heading, we reallocated resources to another portion of the project to continually drive the completion schedule,” Lane said. “Our camp was organized so we could react to unforeseen increase and decrease of personnel as required to accommodate the schedule.”
The project team maintained a 66-person camp, only accessible by boat or floatplane. All materials had to be delivered to the site via barge. Material management was essential and the team had to develop a comprehensive logistics plan to ensure that both the camp and the project site had all the required food, materials, and equipment.
The project team established close working relationships with local suppliers to obtain the necessary fuel, food, and materials, which were delivered by barge twice a week.
This project was procured using the CM/GC contract delivery method, which enabled Kiewit, AKDOT&PF, and the design team to work together to finalize the project scope and optimize the design.
During the preconstruction process, the team collaborated to identify and mitigate risks, maximize the scope of work to meet the project goals within a constrained budget, validate design assumptions, and explore alternative materials and concepts.
As a result of this partnership, the team was able to optimize the original scope of work to provide $25 million in cost savings. The original design included 14 miles of Greenfield Road and five precast bulb tee bridges, and would have cost approximately $59 million.
Kiewit proposed a design that reduced the amount of new road construction to 6.4 miles and included the construction of only one prefabricated steel bridge. These innovations reduced the estimated cost to $34 million.
Given the location and nature of the project, it was difficult to fully ascertain the existing conditions and earthwork quantities. Although a LiDAR survey was conducted, it was only a best estimate of the conditions due to the interference of tall and thick tree cover in the area.
The decision was made to accommodate encountered conditions by adjusting the alignment in areas that would have otherwise required large cuts or fills. This approach contributed to underrunning borrow quantity by almost 30,000 cubic yd, which also reduced costs and provided schedule efficiencies.
The team was also challenged by the presence of large expanses of wetlands and muskeg. The true depths of muskeg and unsuitable material was unknown. By implementing the use of corduroy road, the team was able to avoid hauling unsuitable material.
These corduroy roads were made up of a series of logs laid perpendicular to the direction of travel. The logs were laid in muskeg wetland and covered in borrow material, with the finished road as the top layer.
This innovation eliminated the need to excavate in these areas and allowed for effective construction of the roadway with minimum fill depths, thereby minimizing the impact on the surrounding geography.
Project: Kake Access Road
Location: Kupreanof Island, Alaska
Owners: Alaska Department of Transportation & Public Facilities (ADOT & PF)
Designer: ADOT & PF
Contractor: Kiewit Infrastructure West Co.
Cost: $34 million
Length: 6.4 miles
Completion Date: Oct. 1, 2021