Paving to reduce hydroplaning on Hawai‘i Island’s Daniel K. Inouye Highway underway

As part of the immediate safety improvements being undertaken, the Hawai‘i Department of Transportation is repaving Daniel K. Inouye Highway (formerly Saddle Road) between mile markers 10 and 22.5 to increase the pavement drainage capability and reduce the potential for hydroplaning.

Crews are currently working at mile marker 16.5 to install open-graded friction course in the uphill direction toward the west side, according to a news release from the state department. Paving will continue between mile markers 16 to 19.5 for another 10 days.

Completion is estimated to be in the last week of July 2026.

Paving at the curve at mile marker 22 and mile marker 13.5 will take another 10 days. Completion is estimated to be in the third week of August.

Striping from mile marker 5.5 to 28 will take another 30 days. This will include installing thermoplastic striping with enhanced glass beading that is more visible, especially in wet weather, as well as raised rumble striping.

Temporary glass bead paint is being used with raised pavement markers for the interim until the permanent striping is installed.

The projected completion date for paving and striping is October, and all work is weather-permitting.

The state department has also installed chevron signs in the curves, as well as other signage, to notify drivers of bends and changes in road direction. Additional signs will be installed.

A traffic emergency zone declaration is in effect, which allows the transportation to accelerate procurement and permitting for additional engineering mitigations. In addition to the engineering mitigations, the state Department of Law Enforcement will increase enforcement presence along the route to reinforce good driving behaviors.