Maui County issues no-significant-impact finding for $31.5 million Hāna Highway repairs at Kalepa Point

The Maui County Department of Public Works has issued a finding of no significant impact for a project to repair Hāna Highway at Kalepa Point, where the county’s environmental assessment says continued deterioration would likely dead-end the road at Kalepa and Alelele bridges.

The county estimates the work will cost $31.46 million and take about 20 months.

The department issued the finding in a final environmental assessment that the State Office of Planning and Sustainable Development published Sunday in The Environmental Notice. The finding means an environmental impact statement is not required. The notice’s glossary says the public has 30 days from publication to challenge such a finding in Environmental Court and seek a ruling requiring one.

The road-protection work calls for repairing about 500 feet of concrete rubble masonry wall and undersized rock protection with a hybrid rock rubblemound revetment and reinforced-concrete retaining wall. The revetment would use a two-stone-thick layer of 4- to 6-ton armor stone, with the retaining wall between it and the road. Roadway improvements include repaving about a quarter mile of Hāna Highway between Kalepa and Alelele bridges and replacing the old seaward guardrails with concrete guardrails.

Large waves from Hurricane Iselle damaged the road protection in August 2014, according to the assessment Iselle peaked as a Category 4 hurricane before making landfall on Hawaiʻi Island as a tropical storm on Aug. 8. Witnesses saw waves washing over the road protection and onto the roadway.

The assessment describes the highway at Kalepa Point as in “extreme disrepair in some areas,” with the edge of the road beginning to erode. It says the probable cause of the revetment’s failure was the lack of a properly designed toe structure, which waves likely undermined. Repairing the structure to its 1987 design would not meet current US Army Corps of Engineers standards, the assessment says. The road was first built around 1947 as part of the Hāna Belt Road system.

Without repairs, the assessment says, the condition of the highway “will likely continue to degrade.” It says that would probably dead-end Hāna Highway at Kalepa and Alelele bridges, leaving Hāna Highway from the north as the only access to Hāna town.

The cost estimate is based on the project’s preliminary design. It includes a $3.2 million allowance for possible modifications to bridges along the route so materials and equipment can be delivered safely.

The assessment attributes the 20-month estimate largely to the site’s remoteness and limited access. Crews would have to bring materials, equipment and workers to the site every day. The revetment would use large armor stone boulders averaging 4.85 tons, or 9,700 pounds, each. Kalepa Bridge has a posted weight limit of 9 tons, and the assessment says that limit allows only one boulder to cross at a time.

The assessment evaluated three alternatives to the proposed design. It says taking no action would severely limit access to the Hāna district and to emergency services. A larger revetment using 7- to 12-ton stones could exceed the bridge’s capacity, the assessment says, and would extend 74 feet seaward of the existing guardrail, compared with 55 feet for the proposed design.

The third alternative was a 600-foot, two-lane tunnel through the Kalepa Point headland, which would permanently close the existing road around the point. A feasibility study put the tunnel’s probable construction cost at $10 million to $38.5 million, while cautioning that the preliminary estimate had an approximate accuracy range of minus 50% to plus 100%. The assessment says a tunnel would require substantial additional study and could affect the King’s Trail, a historic paved trail described in the assessment as encircling Maui.

The notice identifies three triggers for environmental review under state law: use of state or county lands or funds, use within land classified as a conservation district, and use within a shoreline area.

Sea Engineering Inc., based in Honolulu, served as the county’s consultant. The notice also lists multiple permits and refers readers to Section 1.5 of the assessment for details.

Questions about the assessment can be directed to Kylie Taketa of the Department of Public Works at 808-270-7745 or kylie.a.taketa@co.maui.hi.us.