Project Description

For many years the idea of connecting Juneau to the mainland via the great highway has been considered. Juneau is the state capitol of Alaska, and is located in the southeastern part of the state. Juneau is unique in many ways, one of which is the fact that currently the only means of getting to Juneau is by air or by boat. This project has been named the Juneau Access Project. Recently, Alaska DOT&PF was given approval to conduct the feasibility study for a portion of this 80-mile high-way that would connect Juneau to Skagway, as well as to the Great Highway system.

Scope of Services

Lachel & Associates, Inc. conducted the feasibility study for Alaska DOT&PF for the proposed tunnel at the northern end of the Juneau Access project into the town of Skagway.

Lachel was retained by the Alaska DOT&PF to review the geology in the area of the proposed Skagway tunnel, to develop preliminary design alternatives relative to tunnel size, grade, ventilation, lighting and operational requirements, and to prepare feasibility level cost estimates.

The town of Skagway is located on a flooded alluvial valley that is bounded by glacially carved granitic bedrock on both sides.

Lachel's investigation identified several suitable portals along the eastern margin of Skagway, with several favorable alignments that conformed to the requirements of Alaska DOT&PF. The tunnel alignment recommendations ranged in length from 5,000 feet to 7,200 feet. Four alternatives were presented to Alaska DOT&PF using the above tunnel lengths, and were either single-lane reversible, or dual-lane bi-directional tunnels.

Client

State of Alaska, Department of Transportation and Public Facilities, Juneau Alaska (Alaska DOT&PF)