Wetland Aviary at Te Wao Nui, Auckland Zoo.
This large walk-through aviary is very grand-looking, although does not really resemble a NZ wetland per se. It contained only New Zealand Scaup and Grey Teal on my visit, but there were signs up for White-faced Heron, and a tank for Long-finned Eel behind where I took the photo. Hopefully more species are added to this exhibit over time (e.g. Sacred Kingfisher, Paradise Shelduck, NZ Shoveller, etc). The fake rock wall at the back conceals the Night Forest nocturnal building.
Te Wao Nui Review here:
http://www.zoochat.com/17/te-wao-nui-review-236615/