The New Zealand Transport Agency decided to apply a second coat to the pavement, following heavy rain last month.
It has to last until early 2013, when a final smooth asphalt surface will be applied over the entire motorway development, including old road surface.
The NZTA plans to have all four lanes of the Caversham Bypass in use by October 5, a few days ahead of an official launch of the project.
More information about the second stage of development, to Lookout Point, should be released next week.