Hāna Highway bridge replacements cleared for construction after environmental review

A project to replace two structurally deficient bridges along Hāna Highway has moved a critical step closer to construction.

The Maui County Department of Public Works has concluded its environmental review for the replacement of the Waikakoi and South Wailua bridges, issuing a finding of no significant environmental impact. The determination confirms that the proposed action is not expected to result in any major adverse effects on the environment, paving the way for the project to proceed.

Project scope and public safety focus

The replacement project addresses the structural deterioration and load capacity deficiencies of the existing spans, a necessary measure to ensure that the Hāna Highway remains safe and fully functional for highway users.

The project, estimated to cost $15.5 million, involves replacing the Waikakoi Bridge (at Milepost 45.4 over Waikakoi Stream) and the South Wailua Bridge (at Milepost 44.6 over Honolewa Stream).

The South Wailua Bridge is located near Wailua Falls, a popular photo spot for visitors. The new bridges will be of a similar size, scale and design to the current structures, maintaining the scenic character of the highway.

The new Waikakoi Bridge is expected to be about 48.5 feet long and 18 feet wide, while the new South Wailua Bridge will be about 60 feet long and 18 feet wide. Both will maintain a single-lane configuration and be built to meet modern design and safety standards.

Managing traffic during construction

To minimize disruption to residents and visitors, temporary bypass bridges will be installed on the ocean side of each existing bridge. These temporary structures will accommodate traffic while the new bridges are under construction.

The overall scope of work also includes necessary improvements to grading, drainage and roadway approaches at both bridge sites. The Department of Public Works is coordinating the effort with the state Department of Transportation. Funding is being provided through the Federal Highway Administration.

Construction is expected to begin in late 2027, with work anticipated to take about one year for each bridge.

Further details regarding the final environmental assessment may be obtained from the project consultant, HDR Inc.