Water Quality · Inner-North Perth

What's actually in
your suburb's water?

Real measurements from Water Corporation's annual testing programme — translated into plain English with honest filter recommendations for your area.

Source: Water Corporation Drinking Water Quality Annual Report 2023–24 · All health parameters within ADWG guidelines

Select your suburb
to see your water data.

Tap your suburb below — we'll show you the Water Corporation data and a plain-English recommendation for your area.

North Perth
Water Corporation locality zone: Mt. Hawthorn  ·  Shares data with North Perth, Leederville, Mount Hawthorn, Highgate, Mount Lawley
Primary water source Gnangara Mound groundwater — Perth's largest aquifer, naturally high in dissolved minerals.
TDS
564mg/L
⚠ Above aesthetic guideline of 500 mg/L
Hardness
110mg/L
Moderately hard · guideline 200 mg/L
pH
7.90
Slightly alkaline · guideline 6.5–8.5 ✓
Chloride
191mg/L
Within aesthetic guideline of 250 mg/L
Sodium
126mg/L
Within aesthetic guideline of 180 mg/L
Turbidity
<0.3NTU
Excellent clarity · guideline 5 NTU ✓

What this means for your home

This area has among the highest TDS of any inner-Perth suburb — slightly above the 500 mg/L aesthetic guideline. You'll likely notice a mineral taste from the tap, scale accumulation on kettles, showerheads, and coffee machines, and possibly a light film on glasses from the dishwasher.

The high mineral load comes from the Gnangara groundwater aquifer — natural geology, not contamination. All health parameters are within Australian Drinking Water Guidelines. Chloride at 191 mg/L contributes to the slightly brackish taste many residents notice. pH of 7.90 is good.

Our recommendation for this area

Whole-home carbon filter — removes chlorine, improves taste and smell at every tap and shower in the house
Under-sink reverse osmosis — strongly recommended given TDS above the aesthetic guideline; removes dissolved solids, sodium, chloride and fluoride for ultra-pure drinking water
Scale-sensitive households will see the most benefit — kettles, coffee machines and hot water systems all last longer with reduced mineral load
Joondanna
Water Corporation locality zone: Mt. Yokine / West Yokine  ·  Shares data with Joondanna, Tuart Hill, Coolbinia, Menora
Primary water source Gnangara Mound groundwater — same aquifer as the inner-north suburbs, comparable mineral profile.
TDS
560mg/L
⚠ Above aesthetic guideline of 500 mg/L
Hardness
103mg/L
Moderately hard · guideline 200 mg/L
pH
7.88
Slightly alkaline · guideline 6.5–8.5 ✓
Chloride
188mg/L
Within aesthetic guideline of 250 mg/L
Sodium
130mg/L
Within aesthetic guideline of 180 mg/L
Turbidity
<0.3NTU
Excellent clarity · guideline 5 NTU ✓

What this means for your home

Very similar water profile to the inner-north suburbs — same groundwater source, comparable mineral levels. TDS of 560 mg/L sits above the 500 mg/L aesthetic guideline. You'll notice scale on appliances and a mineral taste, particularly if you've previously lived somewhere with softer water.

Hardness at 103 mg/L is moderately hard — noticeable but not as severe as Perth's far-northern suburbs like Neerabup (190 mg/L) or Yanchep (204 mg/L). pH ranges 7.28–7.92 in this zone depending on season and supply blend — generally good with slightly more variation than the Mt. Hawthorn zone.

Our recommendation for this area

Whole-home carbon filter — removes chlorine taste and smell from all water entering the home, benefits shower water quality too
Under-sink reverse osmosis — recommended for drinking and cooking given TDS above the aesthetic guideline; gives you clean, neutral-tasting water from a dedicated kitchen tap
Same recommendation as the Mt. Hawthorn zone — the groundwater source drives the same filtration need across both areas
Subiaco
Water Corporation locality zone: Bold Park  ·  Shares data with Subiaco, Wembley, Floreat
Primary water source Mixed supply — greater proportion of desalinated seawater. Noticeably different water profile to inner-north suburbs.
TDS
286mg/L
Well within aesthetic guideline of 500 mg/L ✓
Hardness
62mg/L
Slightly hard · guideline 200 mg/L ✓
pH
7.78
Slightly alkaline · guideline 6.5–8.5 ✓
Chloride
118mg/L
Well within aesthetic guideline of 250 mg/L ✓
Sodium
68mg/L
Well within aesthetic guideline of 180 mg/L ✓
Turbidity
<0.1NTU
Excellent clarity · guideline 5 NTU ✓

What this means for your home

The Bold Park zone has noticeably better water quality than inner-north suburbs. TDS of 286 mg/L is less than half the North Perth/Leederville area value. Hardness at 62 mg/L is only slightly hard, and all aesthetic parameters sit comfortably within guidelines. Less scale on appliances, less mineral taste.

This is largely because the supply mix here includes significantly more desalinated water than Gnangara groundwater. Chlorine is still added — that's consistent across all Perth water — but the mineral profile is much lighter. Honest assessment: your water quality is reasonably good by Perth standards.

Our recommendation for this area

Whole-home carbon filter — worthwhile for chlorine removal, skin and hair benefits, and protecting appliances from any residual scale
Reverse osmosis — optional, not essential. TDS is well within the aesthetic guideline. Whether to add RO is a personal preference rather than a clear water quality concern in this zone
This is one of the zones where we'd be straight with you: a whole-home filter is genuinely worthwhile, but we wouldn't push RO without a good reason specific to your household
Applies to All Suburbs

What's consistent
across every area.

Regardless of which suburb you're in, these parameters apply across all inner-north Perth water supply zones.

ParameterPerth 2023–24ADWG GuidelineWhat it means
Chlorine Present — all zones Within limits ≤5 mg/L (health) Added for disinfection. Taste threshold ~0.6–1.0 mg/L. Longer pipe runs = stronger taste, especially summer. Removed by carbon filter.
Fluoride ~0.75 mg/L avg Within limits ≤1.5 mg/L (health) Added by WA Dept of Health directive. All inner-north suburbs receive fluoridated water. Only reverse osmosis removes fluoride effectively (~90–95%).
Trihalomethanes 0.066 mg/L avg Within limits ≤0.25 mg/L (health) Disinfection byproducts from chlorine reacting with organic matter. Perth sits at 26% of the guideline. Removed by activated carbon filtration.
E. coli Not detected Guideline met Zero detection No E. coli detected across 74,500+ samples in 2023–24. Perth's water is microbiologically safe across all tested zones.
Plain English Guide

What do these
measurements actually mean?

TDS

Total Dissolved Solids — everything dissolved in the water

TDS measures all minerals, salts and metals dissolved in water. Perth's inner-north sits at 560–564 mg/L — slightly above the 500 mg/L aesthetic guideline. Not harmful, but you'll taste it and see it as scale. Sydney's TDS averages 124 mg/L. Reverse osmosis is the most effective way to reduce TDS.

Hardness

Calcium and magnesium content

Hard water leaves white scale deposits on taps, kettles, appliances, and reduces soap effectiveness. The service area ranges from slightly hard (62 mg/L in Subiaco/Wembley) to moderately hard (110 mg/L in North Perth/Leederville). The aesthetic guideline is 200 mg/L.

pH

Acidity or alkalinity of the water

pH 7 is neutral. The ADWG guideline is 6.5–8.5. All inner-north zones average 7.78–7.90 — slightly alkaline, well within the healthy range. Acidic water below 6.5 can leach metals from copper pipes; alkaline above 8.5 can taste bitter.

Chloride

Salt content — different from chlorine

Chloride is a naturally occurring salt mineral in groundwater — separate from chlorine (the disinfectant added for treatment). Inner-north Perth ranges from 118 mg/L (Subiaco/Wembley) to 191 mg/L (North Perth/Leederville). At higher levels it contributes a slightly salty taste. Reduced effectively by reverse osmosis.

Data source and disclaimer

All water quality data is sourced from the Water Corporation Drinking Water Quality Annual Report 2023–24 (testing period 01/07/2023 to 30/06/2024). Values shown are zone mean readings. Individual properties may vary based on pipe age, distance from treatment plant, and seasonal source blending. For complete and current data, visit watercorporation.com.au. Proper Water does not conduct independent water testing — this page presents Water Corporation's own published data. All parameters cited meet Australian Drinking Water Guidelines health standards.

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