ROTORUA · OFFICIAL COUNCIL DATA

What's actually in Rotorua's tap water

Q: Is Rotorua's water fluoridated?

The city supply is - fluoride at 0.60 mg/L typical, peaking at 0.85 in the council's results, 57% of the 1.5 mg/L legal limit. Several village schemes, Ngongotaha among them, are not fluoridated. The free water check tells you which scheme your address is on. No whole-house filter removes fluoride; reverse osmosis removes around 90% of it.

Q: Is Rotorua tap water safe to drink?

Yes, and we'll say it plainly: Rotorua tap water is safe. Not one E. coli detection in 145 city samples across the year. Every metal tested came in at trace levels or below detection. Safe and pure are different questions though. The same results show chlorine at 0.56 mg/L typical and fluoride at 0.60 still in the water at your tap. Both inside the limits, both still there. Filtering is about what you'd choose, not what you should fear.

Q: How much chlorine is in Rotorua's water?

0.56 mg/L typical, peaking at 0.73, across 145 city samples in the year to August 2026. The legal limit is 5 mg/L, so Rotorua sits well inside it. The chlorine is there to disinfect the water on its way through the network. Its work is done by the time it reaches your tap. Taking it out for the whole house is a whole-house filter's job. We supply those by arrangement - call us on 021 709 370.

Q: Why does Rotorua's water sit outside the pH guideline?

The city supply runs at pH 6.5 against the national aesthetic range of 7-8.5. That range is about taste and plumbing, not a health limit. It is not a reason to buy anything. We don't sell neutralisers for it.

Q: What about THMs in Rotorua's water?

Trihalomethanes are by-products that form when chlorine reacts with natural organic matter. A side effect of disinfection, not a contaminant that got in. In the council's quarterly samples for the city supply they were not detected above the lab's reporting limit (below 0.007 mg/L against the 0.06 reference). A genuinely good result, and we'll say so.

Rotorua Lakes Council runs ten supply schemes, and the council's own results show exactly what's in the city's water. Free chlorine at 0.56 mg/L typical, fluoride peaking at 0.85 mg/L, and not one E. coli detection in 145 samples. The water is safe. This page holds a full year of results for the city supply. Several village schemes run differently - the free water check reads yours.

Official council data

Released by Rotorua Lakes Council under official information request REQ26-3110351

August 2025 to August 2026 · scheme-by-scheme results for every supply the council runs

THE HEADLINE NUMBERS

One reading sits above health goals.

Your water passes New Zealand's rules. Rotorua Lakes Council treats its water properly, and their own results on this page show it. The same results show what's still in the water when it reaches your tap. The chlorine that has already done its job, the fluoride that is added on purpose, and the odd trace the network picks up. All measured, all inside the limits, all listed below. What you do about it is up to you, and doing nothing is one of the options.

0.56mg/L

Free chlorine, typical

Peaking at 0.73 across 145 city samples. It keeps the water safe on the way to you, and its work is done by the time it reaches your tap.

0.60mg/L

Fluoride, typical

Added deliberately on the city supply, peaking at 0.85 - 57% of the legal limit. Some village schemes are not fluoridated. No whole-house filter removes it; reverse osmosis is what does.

0

E. coli detections

The primary safety test, 145 samples across the year. The city supply passed every one.

THE FULL RESULTS

What was actually found

Rotorua Lakes Council tests each scheme on a fixed schedule - chlorine, pH, turbidity and E. coli year-round, metals and chlorination by-products a few times a year. These are the combined results for the city's Central and Eastern supplies, the more cautious reading shown wherever they differ, ordered the way the council tests them.

Substance	Reading	Legal limit / guideline	Share of limit
Chemical and Physical
Free available chlorine	0.73 mg/Lpeak, 0.56 typical	5 mg/L as Cl2 (legal limit)	15%
Acidity (pH)	pH 6.5outside the guideline range	7-8.5 (guideline)	-
Turbidity (clarity)	0.45 NTUpeak, 0.21 typical	5 NTU (guideline)	9%
Fluoride	0.85 mg/Lpeak, 0.60 typical	1.5 mg/L (legal limit)	57%
Trace Elements
Lead	0.00035 mg/Lhighest of 4 samples	0.01 mg/L (legal limit)	3%
Zinc	0.0059 mg/Lhighest of 4 samples	1.5 mg/L (guideline)	<1%
Copper	0.0027 mg/Lhighest of 4 samples	2 mg/L (legal limit)	<1%
Cadmium, Chromium, Mercury, Nickel and Antimonytested for, never found	Not detected4 samples each, all below detection	individual legal limits apply	-
Chlorination by-products
Trihalomethanes (total)a by-product of disinfection, not a contaminant that got in	Not detectedbelow <0.007 mg/L, 8 quarterly samples	0.06 mg/L (tightest THM)	-
Haloacetic acids (total)checked against the tightest individual HAA limit	Not detectedbelow <0.03 mg/L, 8 quarterly samples	0.05 mg/L (legal limit)	-
Bacteriological
E. colithe primary safety test - tested year-round, not just quarterly	All clear145 samples, none detected	less than 1 per 100 mL (legal limit)	-

Source: Rotorua Lakes Council LGOIMA response REQ26-3110351, released 11 August 2026. Where no verified legal limit or guideline exists for a reading, no percentage is shown.

WHAT THIS MEANS FOR YOUR HOUSE

Three things worth knowing.

The chlorine's work is already done

Chlorine is added to keep the water safe through the network. By the time it reaches your house, that job is finished. It doesn't need to be in the water you drink and shower in. In the shower it oxidises the natural oils in your skin and hair - measured chemistry, not a health claim. The city supply runs at 0.56 mg/L typically. Taking it out for the whole house is a whole-house filter's job. We supply those by arrangement - call us on 021 709 370.

Only reverse osmosis touches the fluoride

Rotorua's city supply is fluoridated, peaking at 0.85 mg/L in the council's results, and no whole-house filter removes fluoride. Reverse osmosis does - reverse osmosis under the kitchen sink removes around 90% of it. Not all of it, and no honest filter company claims otherwise. Whether you want it removed is your call. The point is that only one kind of filter makes a difference.

Safe and pure are different questions

Rotorua's water is safe, and we'll keep saying so. Not one E. coli detection in 145 city samples, every metal at trace levels or below detection. But limits move. America's regulator set its PFAS health goal at zero last year. Australia cut its own PFAS limits this June, and New Zealand still uses the numbers Australia moved on from. Microplastics and PFAS aren't in the council's testing at all. This year of results includes not one test for either. The city supply also sits at pH 6.5, just outside the national 7-8.5 aesthetic range. That's about taste and plumbing, not a health limit, and not a reason to buy anything. Safe is the council's job, and their numbers show they're doing it. Zero is a choice you make at your own tap.

YOUR ADDRESS

This is the citywide picture. Get the report for your address.

The free water check takes about two minutes, and it includes the PDF water report for your address - written from the same council data, read for your house.

Check my water - free

THE SYSTEM THAT FITS

What we'd fit in Rotorua.

Fluoride, PFAS and microplastics only come out at the kitchen tap with reverse osmosis. That's the ES60's job. If it's the chlorine in your showers that bothers you, that's a whole-house filter. We supply those by arrangement - call us on 021 709 370.

Pentair ES60 under-bench reverse osmosis unit

Under the sink · removes fluoride, PFAS and microplastics

Pentair ES60 under-bench RO

~~RRP $1,748~~ $1,595 Save $398

Genuine Pentair90 day guarantee

The one for the fluoridated city supply. Reverse osmosis removes around 90% of the fluoride at the kitchen tap. Plus the PFAS and microplastics nobody tests for. No tank, and it tells you when filters are due. Ships with the first year's refill free.

View

ROTORUA WATER QUESTIONS

Straight answers.

The city supply is - fluoride at 0.60 mg/L typical, peaking at 0.85 in the council's results, 57% of the 1.5 mg/L legal limit. Several village schemes, Ngongotaha among them, are not fluoridated. The free water check tells you which scheme your address is on. No whole-house filter removes fluoride; reverse osmosis removes around 90% of it.

Yes, and we'll say it plainly: Rotorua tap water is safe. Not one E. coli detection in 145 city samples across the year. Every metal tested came in at trace levels or below detection. Safe and pure are different questions though. The same results show chlorine at 0.56 mg/L typical and fluoride at 0.60 still in the water at your tap. Both inside the limits, both still there. Filtering is about what you'd choose, not what you should fear.

0.56 mg/L typical, peaking at 0.73, across 145 city samples in the year to August 2026. The legal limit is 5 mg/L, so Rotorua sits well inside it. The chlorine is there to disinfect the water on its way through the network. Its work is done by the time it reaches your tap. Taking it out for the whole house is a whole-house filter's job. We supply those by arrangement - call us on 021 709 370.

The city supply runs at pH 6.5 against the national aesthetic range of 7-8.5. That range is about taste and plumbing, not a health limit. It is not a reason to buy anything. We don't sell neutralisers for it.

Trihalomethanes are by-products that form when chlorine reacts with natural organic matter. A side effect of disinfection, not a contaminant that got in. In the council's quarterly samples for the city supply they were not detected above the lab's reporting limit (below 0.007 mg/L against the 0.06 reference). A genuinely good result, and we'll say so.