A new pedestrian bridge is forming under the cover of darkness at Pescara Point near Papakura.
The first piece of a structure that will stretch over the Southern Motorway was lifted into place in overnight work on Thursday.
A curved bridge will span 106m, connecting coastal paths beside the Manukau Harbour and Pahurehure Inlet, and also to local roadside footpaths.
NZ Transport Agency project delivery senior manager Andrew Thackwray says the heavy rain didn't hinder the first installation of the bridge section.
But he warned motorists to take care that they weren't distracted by the bridge taking shape and the extra activity around the work site.