H-1 Freeway construction remains an important transportation issue for Oahu drivers in 2026. Multiple improvement projects are underway along different parts of the corridor, including pavement rehabilitation, freeway widening, resurfacing, striping, guardrail work, and other infrastructure improvements.
Because Interstate H-1 connects Honolulu with communities across central and western Oahu, construction in one area may influence travel well beyond the immediate work zone. Drivers may encounter temporary lane closures, ramp restrictions, changing traffic patterns, and slower travel during scheduled work periods.
Understanding where projects are taking place and knowing where to check current closure information can help motorists better prepare for trips along one of Hawaii’s most heavily used highways.
Why Is There So Much Construction on H-1?
Interstate H-1 is a major transportation corridor serving Honolulu and communities across southern and western Oahu. Maintaining a heavily traveled freeway requires ongoing pavement repairs, resurfacing, safety improvements, bridge work, drainage work, striping, and upgrades to aging infrastructure.
In 2026, the Hawaii Department of Transportation is continuing several major projects throughout the H-1 and H-201 freeway system. These projects are occurring in different locations and have different completion schedules.
Drivers looking for broader information about the island’s road network can also visit our Hawaii Roads guide.
Where H-1 Construction Is Taking Place
Makakilo and Kunia Pavement Rehabilitation
One ongoing project involves pavement rehabilitation around the Makakilo and Kunia interchanges. The work includes removing deteriorated concrete pavement and replacing sections with precast concrete panels.
The broader H-1 and H-2 pavement rehabilitation project includes work on H-1 in both directions at Makakilo and Kunia, along with work near the H-1 and H-2 interchange.
Nighttime lane closures may be used for concrete demolition and panel installation. Because schedules can vary, drivers should check current Hawaii Department of Transportation notices rather than assuming the same lanes are closed each week.
Why Precast Concrete Panels Are Used
Precast panels allow damaged pavement sections to be replaced with concrete components manufactured before installation. This approach can support major pavement rehabilitation while concentrating portions of the work into scheduled construction periods.
Salt Lake Pavement Rehabilitation
The H-1 Salt Lake pavement rehabilitation project has also remained active in 2026. Work has included pavement reconstruction, striping, signs, rumble strips, and other finishing improvements between the Pearl Harbor Interchange and the Salt Lake area.
Some phases have required substantial weekend lane reductions. Temporary closures in this part of the freeway can affect traffic traveling between central Oahu, the airport area, and Honolulu.
Eastbound H-1 Improvements Near Kalihi
Another major project involves the eastbound H-1 corridor from around the Ola Lane Overpass toward the Likelike Highway off-ramp.
The project includes freeway improvements and supporting work on nearby streets. Utility relocation, temporary pedestrian infrastructure, retaining wall work, and related construction have required traffic controls around the corridor.
This project is particularly relevant to drivers heading toward urban Honolulu because the freeway passes through densely developed neighborhoods where alternate road capacity can be limited.
Resurfacing and Street Improvements Near Central Honolulu
Work associated with the H-1 corridor between the Miller Street pedestrian overpass and the Kapiolani Boulevard interchange also continues through associated streets, ramps, overpasses, pavement markings, guardrails, and lighting improvements.
Areas around Kinau Street, Ward Avenue, Punahou Street, McCully Street, and nearby freeway connections may experience scheduled work as crews move through the project area.
How H-1 Construction Can Affect Traffic
Highway construction does not need to completely close a freeway to influence traffic. Even a single closed lane can require vehicles to merge and may reduce the amount of traffic that can move through an area at one time.
Ramp closures may also change travel patterns. Drivers who normally enter or exit at a particular location may need to use another interchange, placing additional vehicles on nearby streets.
Construction activity can have a wider effect during busy commuting periods. Traffic approaching a work zone may begin slowing well before the actual closure, particularly when several lanes merge into fewer travel lanes.
For general information about congestion and commuting around the islands, visit our Hawaii Traffic page.
Ways Drivers Can Prepare for H-1 Roadwork
Check the Weekly HDOT Closure List
The Hawaii Department of Transportation publishes an official weekly list of planned Oahu lane closures. The schedule identifies roadwork locations, directions of travel, closure periods, and the type of work being performed.
Drivers can review the latest information through the HDOT Oahu Lane Closures page.
Check Current Freeway Cameras
GoAkamai provides traffic camera views along many sections of Interstate H-1, including locations around Makakilo, Kunia, Waikele, Pearl City, Salt Lake, the airport, downtown Honolulu, Punahou, University Avenue, and other points along the freeway.
Before leaving, motorists can check GoAkamai traffic cameras to get a better sense of current roadway conditions.
Allow Flexibility in Your Route
Drivers traveling through a construction area may want to allow additional time, particularly when lane reductions or ramp closures are scheduled.
An alternate route may help in some situations, but nearby surface streets can also become busier when freeway traffic shifts away from a work zone. Checking conditions shortly before departure provides more useful information than relying only on a familiar route.
Pay Attention to Temporary Traffic Controls
Construction zones may introduce temporary lane markings, concrete barriers, signs, reduced shoulders, or unfamiliar merging patterns.
Motorists should watch the roadway carefully and follow posted traffic controls as they move through active work areas.
Our Driving in Hawaii guide provides additional information about local roads, highway driving, weather, and changing roadway conditions.
How Long Will H-1 Construction Continue?
There is no single completion date for all H-1 construction because several separate projects are underway.
HDOT reported in June 2026 that the H-1 and H-2 pavement rehabilitation project was expected to continue into March 2027. The Salt Lake rehabilitation project was approaching completion in 2026, while the eastbound H-1 improvement project near Kalihi had an estimated completion date in 2028, subject to weather and other project conditions.
Other resurfacing and improvement work around central Honolulu also has its own schedule.
This means Oahu drivers may continue encountering construction along different portions of H-1 even after work in one area is completed.
H-1 Construction Is Part of an Evolving Freeway System
Interstate H-1 remains central to everyday transportation across Oahu. Maintaining and improving such a heavily used corridor involves work that can temporarily change traffic conditions while projects are underway.
For drivers, the practical approach is to stay aware of where construction is occurring, check official closure schedules, review current traffic conditions, and expect traffic patterns to change as projects move from one phase to another.
HDOT notes that construction schedules are weather dependent and may change without advance notice. Current weekly roadwork information should therefore be checked before relying on a specific closure schedule.
For more information about Oahu highways and local driving, browse our traffic, driving, and transportation articles.