Wairau Valley is a suburb of Auckland, New Zealand. The area is predominantly light industrial/commercial. The Northern Motorway passes to the east, and the Wairau Park shopping complex extends to the north. The valley is drained by the Wairau Creek, which flows on through Milford and discharges into the Hauraki Gulf from an estuary at the northern …Wairau Valley is a suburb of Auckland, New Zealand. The area is predominantly light industrial/commercial. The Northern Motorway passes to the east, and the Wairau Park shopping complex extends to the north. The valley is drained by the Wairau Creek, which flows on through Milford and discharges into the Hauraki Gulf from an estuary at the northern end of Milford Beach.