After the introduction of the Freedom Camping Act in 2011 the Westland District Council became very aggressive at issuing $200 instant fines to anyone camping in prohibited areas which is pretty much all non-Dept of Conservation public land on the West Coast. The good news in 2015 is that the Westland District Council have abandoned their policy of issuing instant fines for freedom camping. You can now safely freedom camp on any public land administered by the WDC. You will easily find a beautiful spot beside the ocean, a lake or river.
There are also many Department of Conservation basic camping areas on the West Coast that charge only a few dollars. They have a toilet and sometimes a water tap.