Australian tap water by city: what is in it, compared
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Eleven Australian cities compared: hardness, chlorine or chloramine, fluoride, and which filter each needs. From the utilities' own reports, with a page for most of them.
Which filter to buy depends on which city you live in more than on any brand. This is the summary; each city has its own page with detail and picks.
The comparison
| City | Hardness (mg/L as CaCO₃) | Disinfectant | Fluoridated | What it means |
|---|---|---|---|---|
| Melbourne | About 31 average, 8 to 108 across zones | Chlorine; chloramine in western and growth areas | Yes | Softest in the country. Filter for taste only, unless your zone is chloraminated. |
| Sydney | About 43 average, hardest zone under 60 | Mostly chlorine; chloramine in some systems | Yes | Soft and easy. Any carbon filter handles it. |
| Brisbane | Moderate, varies by zone and season | Chloramine (Brisbane, Ipswich, Logan, Moreton Bay) | Yes | Chloramine changes everything: catalytic carbon and vitamin C, not standard media. |
| Adelaide | About 130 to 200, higher in summer | Chloramine across the metro area | Yes | Hard and chloraminated. Reverse osmosis at the kitchen, vitamin C in the shower. |
| Perth | About 100 to over 200, hardest of the capitals | Free chlorine | Yes | Very hard but easy to filter for taste. Scale needs a softener. |
Figures are the utilities’ published typical values; every city varies by supply zone and season. Check your own zone in your utility’s current water quality report before buying.
Six more cities and regions
| City | Hardness (mg/L as CaCO₃) | Disinfectant | Fluoridated | What it means |
|---|---|---|---|---|
| Gold Coast | 37 to 58, average 47 (City of Gold Coast 2024–25) | Chlorine | Yes, average 0.75 mg/L | Soft and chlorinated, unlike Brisbane. Standard filters work. |
| Sunshine Coast and Noosa | 20 to 102, average 61 (Unitywater North zone results) | Chlorine on Unitywater’s published results: free chlorine about 1 mg/L, monochloramine below detection | Yes, average 0.74 mg/L | Soft to moderate and chlorinated, unlike Brisbane and Moreton Bay. Standard filters work; check your postcode on Unitywater’s site. |
| Newcastle and Hunter | 46 to 74, median 56 at Grahamstown (Hunter Water, Aug 2025) | Chlorine | Yes, about 0.99 mg/L | Soft, non-scaling in Hunter Water’s words. Filter for taste or fluoride only. |
| Canberra | 21 to 59, average 37 (Icon Water 2024–25) | Chlorine and UV; chloramine not used | Yes, average 0.79 mg/L | Soft. Icon Water does not recommend filters; RO only for fluoride. |
| Hobart | Not published as a single figure; check TasWater’s portal by suburb | Chlorine | Yes, 0.8 to 1.1 mg/L | Chlorinated; standard filters work. Check your suburb before buying for scale. |
| Darwin | Varies with the dam and bore blend; Power and Water calls NT groundwater hard | Chlorine, minimum 0.5 to 0.6 mg/L | Yes, under 1 mg/L | Higher chlorine residual by design; RO for hardness and fluoride at the tap. |
Reading the table
Hardness below 60 is soft, 60 to 120 moderate, 120 to 180 hard and above 180 very hard. Hardness is minerals, not contaminants; it scales kettles and coffee machines and makes soap lather poorly. No cartridge filter removes it. Reverse osmosis does at one tap; a softener does for the house.
Disinfectant decides your filter media. Chlorine is easy: any carbon or KDF filter removes it. Chloramine is stable and needs catalytic carbon for drinking water and vitamin C for showers. Buying a standard filter in a chloramine city is the most common mistake in this whole category.
Fluoride is in every city listed. It passes straight through carbon. Reverse osmosis removes most of it.
Filter by city, in one line each
- Melbourne and Sydney: a water filter jug or on-tap filter for taste; RO only if fluoride matters to you.
- Brisbane: catalytic carbon under the sink, vitamin C shower filter.
- Adelaide: reverse osmosis at the kitchen tap, vitamin C shower filter.
- Perth: reverse osmosis for scale and fluoride at the tap, a plumber-installed softener if scale everywhere is the problem.
Sources: Seqwater and Urban Utilities; Unitywater water quality results by postcode; City of Gold Coast Drinking Water Service Annual Report 2024–25; Hunter Water; Icon Water; TasWater; Power and Water; Sydney Water; Melbourne Water and the Melbourne retail water businesses; Water Corporation; SA Water; Australian Drinking Water Guidelines (NHMRC). The postcode lookup gives the same figures by postcode.
Frequently asked questions
Which Australian city has the hardest water?
Perth, with many zones above 200 milligrams per litre, followed by Adelaide at roughly 130 to 200 depending on the River Murray share of the blend. Melbourne is the softest at around 30, then Sydney at around 43. Brisbane sits in the middle and varies by zone.
Which cities use chloramine?
Brisbane, Ipswich, Logan and Moreton Bay on the Seqwater grid, and metropolitan Adelaide. Melbourne uses it in western and growth-area systems, and Sydney in some delivery systems. Perth uses free chlorine, and so do Canberra, Hobart, Darwin, Newcastle, the Gold Coast (according to the City's own 2024–25 report) and, on Unitywater's published results, the Sunshine Coast. Chloramine matters because standard carbon and KDF filters remove far less of it than they do of chlorine.
Is all Australian capital-city water fluoridated?
Yes, all five mainland capitals fluoridate. Carbon filters do not remove fluoride; reverse osmosis does.
Is Australian tap water safe to drink?
Yes. Every capital treats to the Australian Drinking Water Guidelines set by the NHMRC. People filter for taste, chlorine or chloramine smell, scale, or to remove fluoride by choice, not for safety.