This is a mystery bonus cache for the Let's Play in Palmy Adventure Lab cache which requires you to complete the Adventure Lab first to obtain the coordinates to locate this cache.
This park also had a Let's Play Palmy Passport post but it's been vandalised, and thrown into the wetlands pond.
Personally I reckon this is a great park for walking the dog off-leash, watching wildlife or taking a picnic.
The cache is at S 40° 20.ABC E 175° 37.XYZ where the Adventure Lab journal will reveal the missing digits.