1) What’s happening on the Pearl City viaduct?
The Hawaii Department of Transportation (HDOT) is repairing deteriorated sections of the concrete bridge deck. Engineering surveys have identified sections along the H1 outbound and the H1 inbound on both the Pearl City and Waimalu viaducts that require replacement. The areas now under repair are being done in advance of the PM Contraflow improvements.

The contractor is using hydro demolition as the method to remove the existing concrete. Fast setting concrete is used as a replacement, which allows the freeway to reopen by 4:30 am.

2) What is hydro demolition?
Hydro demolition uses high pressure (20,000 psi) water jets to remove the existing concrete without damaging the reinforcing steel (rebar) and the remaining concrete areas. Wood forms are then installed, followed up by the pouring of the fast setting concrete. The fast setting concrete needs only three hours to cure to allow for traffic to pass.

3) Why are the detours so long?  There are areas that are closed and no one is working nearby?  Can’t the detours be shortened?
The contractor is required to follow the federal requirements in the Manual of Uniform Traffic Control Devices (MUTCD) when implementing the detour. These detours are developed by a design engineer and approved by HDOT. Along the freeway, MUTCD requires a buffer area of 2100 feet for each lane that is closed before the work area to provide the workers with a safe working zone. The contractor is allowed to close three (3) lanes to provide a safe working zone and a lateral buffer between the construction and passing vehicles.

4) Why is the work done at night and not during the daytime?
The volume of traffic during the daytime hours is high and closing the required number of lanes to provide a safe work zone would create a tremendous traffic jam. This would adversely affect the traveling public and businesses along the route and businesses that travel along the H1 in both directions. To reduce the impact to the public, the HDOT has allowed the contractor to work extended hours on selected Sundays as a means of expediting the project.

5) How many more Sundays will there be lane closures?
As activity on the deck widening portion increases, day time Sunday lane closures will be instituted on a case-by-case basis by the DOT. If approved, notices will be issued through the DOT, posted on this website and goakamai.org.

6) Where can I call for information?
There is a 24 hour hotline at (808) 735-7434. There is also an email contact form.