In general, do I need to treat water in NZ?

I've never treated water. AFAIK Giardia Isn't a problem in the south island.

It is an interesting question and the answer although simple might not make sense. Water in a forest park or National park (with the exception of volcanic water) and water in streams that have not passed through farmland or urban areas is generally safe to drink if it is clear free flowing and not turbulent. Thats what most of us expect the water to be and that is how most of us see the lack of need to treat it. The truth in statistics muddys the water somewhat. In the Tararua Forest park every river tests positive for giardia but I know absolutely no one that either treats the water or has ever got giardia. I do know someone who got giadia from a treated municipal supply drawn from a Tararua river though which sort of proves that a: giadia is there and B: town water treatment doesnt always kill it. You could see it as risk management the risk is there but for us a giadia infection means a couple of days off work. Im guessing it would ruin your holiday so the consequences are much higher so buying a filter might make sense. I would suggest buying a filter before coming here. They are expensive here because they dont sell well

I've never treated water, from streams, rivers, stagnant tarns or hut tanks.

Yeah I was also wondering about tarns as they are stagnant. That is so different from the USA where everybody takes and uses a filter. I see what you mean buy expensive - the MSR Guardian is $600. Surely one would only need this in a third world country or if your drinking from a farm creek

Hi. Usually it really depends where you get the water from... If is a current water stream its fine..but if you get from an area close to farms where animals are or the water has been there for long time...well personally I wouldn't drink it without treatment. Hut tanks are fine as well as gaiters suggested too.

Hi, you would probably get away with not treating water in more remote spots where comparatively few people go e.g. Dusky Track etc. I would definitely treat water at the huts, on the great walks and in the more popular tramping areas. It only takes a couple of minutes to filter water and is better to be safe than sorry. I have been using the Sawyer Mini filter on solo trips and the Platypus Gravity works for trips with 2 or more people to great success. There are not overly expensive and well worth the investment. Having previously been a hut warden I was constantly amazed at what I saw people doing in and around streams, lakes and other water supplies.

generally you don't need to treat water, unless there are farm animals that have access to the water upstream from where you are. places like the wanganui river, treat the water from the river if you have to get if from the river but if you're getting if from water coming straight out of a forest , you won't have to treat it busy parks you may have to treat the water, i wouldnt trust water taken from a stream on the coast of the abel tasman track, too many people duck into the bush to go to the toilet close to water sources and don't dispose of it properly i've almost never heard of people getting sick in the main conservation parks except for situations like the ones I've mentioned above... recently a lot of people were getting sick at huts in the nelson lakes but that was attributed to norovirus in the huts and not contaminated water.

I dont generally treat water however Im still not sure on the position of getting water from tarns. If I have no choice but to get water from a little-used hut tank that has signs of rodent infestation then I would definitely treat the water. Lepto is a real thing. Otherwise, from rivers, streams etc, I have never treated it.

I've never bothered to treat water. I've drunken out of small tarns before, its more the taste that puts me off.