The Whangaparaoa Peninsula is a suburban area about 25 kilometers north of Auckland, New Zealand. “Whangaparoa” is Maori for “Bay of Whales” and pods of orcas and dolphin are regularly spotted in the waters off the peninsula. However, dolphin and whale sightings were the last things on the minds of a team of concrete cutters from A1 Kiwi Concrete Cutters and Lowery and Sharp Concrete Cutters who recently joined forces to complete a lighting and signage project for better traffic management on Whangaparaoa Road.
Whangaparaoa Road is a narrow main arterial route, servicing the ever-expanding population, now estimated to top 40,000, on the Whangaparaoa Peninsula. The peninsula has seen an increase in population as it has become an attractive bedroom community for commuters. There has been a two lane road, one lane each way, servicing the Peninsula, which gets congested in the morning and afternoon peak driving times. The road is wide enough to feature a third lane so the solution to ease the flow of traffic was to control the third lane at peak times.
For the upgrade, during the morning rush hour, two lanes would be used heading in to Auckland and in the afternoon two lanes would be used heading away from Auckland. To help drivers stay in the correct lane, seven overhead gantries would be erected and lane lights to direct drivers, were to be installed into the road. The lane lights would be powered by induction, therefore there would be no direct wiring of the lights to the power cable and they would have the ability to change color depending on power frequency.
Because the major portion of this project consisted of signage and lighting, the work of a concrete sawing and drilling company was required. New Zealand CSDA member, A1 Kiwi Cutters won the contract which was to cut the trench for a power cable, drill the holes in the road for the lights, control and clean slurry out of the trench prior to the cable installation and dispose of the slurry. The specifics of this cutting and drilling project included 4,196 meters (13,766 feet) of trench, 8 millimeters (.31 inches) wide and 60 millimeters (2.36 inches) deep and 1371 holes, each 117 millimeters (4.61inches) in diameter and 85 millimeters (3.35 inches) deep. In addition, at the positions where the trench intersected a hole, the trench width was increased to 12 millimeters (.47 inches) and deepened to 85 millimeters (3.35 inches). This was extended by 150 millimeters (5.90 inches) on either side of each hole. These dimensions made it easier for removal of the cores.
The time constraint for completing this project was a critical piece of this job as the client wanted the project to be completed during the night, and in only seven shifts. Work hours were scheduled from 8:00 PM to 1:00 AM, when traffic would be at its lightest. This was a working time of just about five hours per shift. This schedule allowed for cleaning out the holes and trench, drying of the holes and trench, installing the cable and lights and sealing of the trench so that the road could be re-opened each morning by 4:00 AM in time for the morning peak traffic.
Completing this amount of work in a very short period of time was beyond the equipment and labor resources A1 Kiwi had available at the time, so NZCSDA member Lowery and Sharp Concrete Cutters was contacted to assist A1 Kiwi. The two companies working together supplied a total of three concrete cutters, five core drillers, three vacuum trucks, and four laborers to break out cores and generally keep the site tidy. In addition, five water blasters were used on the project.
The work was completed in the required seven shifts although the cutting and drilling component went more quickly than the installation portion of the job so there was a break after three nights of work to allow the other contractors to catch up. There were several additional shifts completed by a smaller crew as there were a couple of issues that needed to be resolved when the trench began to close up.
The project went well from the perspective of all involved, A1 Kiwi Cutters, Lowery and Sharp Concrete Cutters and the client with a successful outcome. The proof of a job well done will ultimately be better traffic flow for Whangaparaoa residents during rush hour, both morning and evening.