Water hardness in Sydney
47 mg/L soft
Tap water in Sydney is soft: 47 mg/L (2.7 gpg · 2.6 °dH · 4.7 °fH).
Source: Sydney Water, Water analysis by delivery system (latest quarterly results) (2026) · data checked 2026-10-23
Range across supply zones: 28–67 mg/L.
12 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| mg/L | mg/L | ||
|---|---|---|---|
| Cascade (Blue Mountains) Water Delivery System | 51 | 51 | soft |
| Macarthur Water Delivery System | 44 | 44 | soft |
| Nepean Water Delivery System | 34 | 34 | soft |
| North Richmond Water Delivery System | 35 | 35 | soft |
| Orchard Hills Water Delivery System | 64 | 64 | moderately hard |
| Potts Hill Water Delivery System | 46 | 46 | soft |
| Prospect East Water Delivery System | 47 | 47 | soft |
| Prospect North Water Delivery System | 52 | 52 | soft |
| Prospect South Water Delivery System | 47 | 47 | soft |
| Ryde Water Delivery System | 49 | 49 | soft |
| Warragamba Water Delivery System | 50 | 50 | soft |
| Woronora Water Delivery System | 45 | 45 | soft |
Sydney's tap water comes mainly from Warragamba Dam and the Upper Nepean dams, and most of it is filtered at the Prospect plant. The figure shown, 46.8 mg/L CaCO₃, is the median across 12 supply zones, which range from 28.0 to 67.0 mg/L, so it depends on which zone your street is in. Scale builds up slowly, so a softener is rarely needed.
Australian Drinking Water Guidelines: aesthetic target ≤ 200 mg/L CaCO₃.
Water data
| Total hardness | 47 mg/L |
|---|---|
| Utility | Sydney Water |
How Sydney compares
- Tap water in Sydney is 45 % softer than the median of the 307 cities we track in Australia (85 mg/L).
- By hardness it ranks 245 of 307 in Australia (1 = hardest); 20 % of these cities have softer water.
- In New South Wales it is number 12 of 13 cities; the regional median is 93 mg/L.
Ranking of the hardest and softest water in Australia →
What it means at home
- Little or no limescale in kettles, water heaters or washing machines.
- Soap lathers easily; water does not dry skin or hair.
- Dishwasher: salt setting at minimum or off.
- No softener needed; a jug filter only changes taste.
How much salt will you use for softening?
No. Water this soft does not need softening.
Descale a coffee machine or kettle about every 6 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Sydney
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 3 °dH |
| AEG / Electrolux | 1 |
| Beko | 1st |
| Hoover | S0 |
| LG | H0 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Sydney water hard or soft?
It is soft: 47 mg/L as CaCO₃ (2.7 gpg, 2.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Sydney safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Australian Drinking Water Guidelines: aesthetic target ≤ 200 mg/L CaCO₃.
How many grains per gallon is Sydney water?
2.7 gpg, equal to 2.6 °dH, 4.7 °fH or 47 mg/L calcium carbonate.
What dishwasher salt setting should I use in Sydney?
For 47 mg/L (2.6 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Sydney?
No. With soft water a softener adds nothing.
Source
Source: Sydney Water, Water analysis by delivery system (latest quarterly results) (2026). Method: computed from supplier's calcium and magnesium. Sydney Water, Water analysis by delivery system (latest quarterly results) · Outdated figure? Tell us