DOT is proposing to improve about a 6-mile stretch of Honoapiilani Highway in West Maui to provide “a safe and reliable transportation facility and to reduce risks and vulnerability to coastal hazards,” according to the Office of Planning and Sustainable Development’s Environmental Notice last week.

The goal is to also alleviate congestion and accommodate future travel demands, as well as complement surrounding conservation work that intends to protect natural resources.

“Strengthening and reinforcing the highway’s reliability will improve the efficiency of not only daily travel demands important to island residents, businesses, and visitors, but also critical emergency response services,” the report said.

Given the seasonal high surf, king tides, stormwater runoff and the predicted 3.2-foot sea level rise that is undermining the roadway, the proposed project aims to address the section from Mile Post 11 in the vicinity of Ukumehame Beach and Mile Post 17 at the southern terminus of the existing Lahaina Bypass in the vicinity of Launiupoko, south of Lahaina town.

The Hawaii Department of Transportation is proposing to improve around a 6-mile stretch of Honoapiilani Highway using one of four alternatives, which involves the construction of a new highway largely along a different alignment. Hawaii Department of Transportation photo

The project site would be 3/4-mile wide inland from the current highway alignment, covering the coastal plain in this area, the report said.

In the Statewide Coastal Highway Program Report, the Olowalu segment and the Ukumehame segment of Honoapiilani ranked No. 2 and No. 12, respectively, on DOT’s list of priority projects to address coastal erosion.

Shorelines in these areas have been eroding an average of between 1.4 feet per year and 1.9 feet per year, according to University of Hawaii’s School of Ocean and Earth Science and Technology Coastal Geology Group.

DOT issued a notice to invite public input on the proposed project and to let the public know that an environmental impact statement will be prepared in the future to study potential improvement options.

A preferred action among four possible alternatives for the improvement project has not been identified yet, but is anticipated to involve construction of a new highway largely along a different alignment.

All alternatives would move at least a portion of the highway inland, away from the existing coastline and projected sea level rise flooding areas. On the Launiupoko end, all alternatives would connect the improved Honoapiilani Highway with the Lahaina Bypass.

Proposed project plans align with the county’s 2022 West Maui Community Plan Update and the 2005 Pali to Puamana Parkway Master Plan.

Depending on which alternative the state chooses, private property acquisitions may be needed, but the improved highway would stay within the existing highway right-of-way and/or within county- and state-owned properties where feasible.

In Launiupoko and Olowalu, all alignments made would require private property acquisitions. In Ukumehame, most properties immediately mauka of the highway are government-owned, so there would be little to no private property purchase in that area. Farther mauka in Ukumehame, improvements would require significant acquisition of private property.

Furthermore, the project may affect areas currently in use or proposed for future residential, commercial, public facility, agriculture and/or parklands uses, the report said.

Other improvement actions and alternatives may be developed further following input from the scoping process and public meetings, the report noted.

Honoapiilani Highway is the main travel route for residents and visitors to get to and from West Maui — it connects the region to big hubs, like Kahului Airport, Kahului Harbor, Maui Memorial Medical Center and other medical services, Costco, as well as other resources not readily available in Lahaina, Kaanapali, Napili, Kapalua and Kahana.

“As the only access to this part of the island, roadway closings and delays carry severe consequences to West Maui residents and the economy,” the report said. “Because there is no other route to central Maui, even slowing traffic along this stretch can have significant effects on the movement of people and freight, including access for emergency vehicles, missed flights, and travel time delays for motorists.”

Additionally, portions of the existing Honoapiilani Highway alignment are located in coastal flood hazard zones identified by the Federal Emergency Management Agency.

Another repair project is currently in development to address erosion where 4,100 feet of highway fronting Ukumehame and 1,000 feet of highway fronting Olowalu will be shifted 8 to 12 feet inland.

However, these projects are short-term fixes as they only address the most severe locations where the road is already undermined.

Due to the scope, scale and complexity of improving the resiliency of a single two-lane coastal highway, which may involve constructing a whole new highway along a different alignment, the project could have significant environmental, cultural, historic, archaeological, recreational and community impacts, according to the notice.

Because DOT and the Federal Highway Administration have determined that this project may have significant impacts, DOT/FHWA and cooperating agencies will prepare an environmental impact statement next year following public feedback next month.

A public hearing is anticipated for December 2023, followed with a 45-day public comment process.

Then, in 2024, a possible final EIS will be published with construction to break ground in 2025.

State and federal funds will be used for this project. However, the estimated project costs for any building alternative exceeded the limited funding available. A projected cost was not included in the report.

The project was awarded a U.S. Department of Transportation Rebuilding American Infrastructure with Sustainability and Equity grant to assist with funding.

Two virtual public meetings will be held via Zoom from noon to 2 p.m. and 6 to 8 p.m. on Dec. 14 and in person from 6 to 8 p.m. on Dec. 15 at the Lahaina Civic Center located at 1840 Honoapiilani Highway.

For more information on the proposed project or to provide comments, visit www.Honoa piilaniHwyImprovements.com.

* Dakota Grossman can be reached at dgrossman@mauinews.com.