The published coordinates take you to a fairly new information board. There's lots of information about the conservation efforts in Marsden VAlley as well as information about the many walking and biking tracks in the area.
Use information from the board to determine the location of the cache.
A = Birchwood Primary
B = Broadgreen Intermediate - (Richmond Primary + Waimea Intermediate)
C = Auckland Point Primary
D = (Kiwi Conservation Club + Victory Primary) - (Tahunanui Primary - Nayland Primary)
E = Henley Primary
F = Nelson College for Girls + Victory Primary
In case you can't find the sign, use this link https://smartstory.nz/stories/conservation-action/
The cache is located at S 41 1A.BCD E 173 1C.AEF
The cache is a bison with log only so BYO writing device.
Enjoy.