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Two Rocks

Perth Region · Western Australia ·  Reporting period 2023-2024

The verdict

Two Rocks's water is much clearer and much closer to neutral pH — though it runs much harder than most of its 27 neighbours.

Compared with 28 localities1 aesthetic reading above ADWG
Two Rocks · Perth

At a glance

Position within the Perth Region

Purity

By-products & nitrate

Around average

About average for the Perth Region

Clarity

Turbidity, colour, metals

Top 1%

Clearer than 100% of Perth Region supplies

Taste

Sodium, chloride, TDS

Around average

About average for the Perth Region

Hardness

Calcium & magnesium

Harder

Harder than 86% of Perth Region supplies

pH balance

How close to neutral (7.0)

Top 11%

More neutral than 89% of Perth Region supplies

Full readings

Typical (mean) value at Two Rocks versus the Perth Region average.

Purity & health
ParameterTwo RocksRegion avgUnit
Trihalomethanes (THMs)0.010.07mg/L
Nitrate4.02.3mg/L
Clarity & appearance
ParameterTwo RocksRegion avgUnit
Iron0.000.03mg/L
Taste & saltiness
ParameterTwo RocksRegion avgUnit
Sodium57.085.0mg/L
Chloride106142mg/L
Total Dissolved Solids (TDS)535400mg/L
Sulphate16.019.4mg/L
Hardness & scale
ParameterTwo RocksRegion avgUnit
HardnessAbove ADWG22895.7mg/L
Alkalinity21083.8mg/L
Silica11.58.9mg/L
pH balance
ParameterTwo RocksRegion avgUnit
pH7.67.8pH units

Data & methodology

Data source: Water Corporation of WA Drinking Water Quality Annual Report 2023-2024.

Regional ranking: Each measured parameter is ranked against every other locality in the Perth Region using the typical (mean) reading. Lower readings rank better, except pH where the score is distance from neutral (7).

ADWG safety check: Every reading is independently checked against the NHMRC Australian Drinking Water Guidelines; any value above the limit is flagged regardless of how it compares to neighbours.