Zetland Water Hardness & Quality Report (2026)

Zetland's drinking water is supplied by Sydney Water, treated at the Prospect Water Filtration Plant incorporating a high Hawkesbury-Nepean component for the City of Sydney LGA southern distribution in New South Wales. Water hardness in Zetland is measured at 168 mg/L — classified as moderately hard — within the Australian Drinking Water Guidelines (ADWG) aesthetic guideline of 200 mg/L published by NHMRC. Zetland — a rapidly growing inner Sydney apartment precinct in the southern City of Sydney LGA within the Green Square urban renewal corridor, known for the Green Square Town Centre, the Harold Park and Gunyama Park Aquatic Centre, the major mixed-use apartment towers transforming this former industrial zone, and the large Zetland–Waterloo residential growth community — receives moderately hard supply, dramatically harder than the soft Redfern sub-zone (60 mg/L) in the same City of Sydney LGA, confirming the dramatic supply blend variation possible within the same LGA.

Zetland's hard supply reflects a high Hawkesbury-Nepean component in the southern City of Sydney LGA Prospect distribution blend. The southern Green Square corridor is supplied through a different distribution main routing, receiving a much higher Hawkesbury-Nepean fraction than the softer northern City of Sydney inner sub-zones. The Hawkesbury-Nepean traverses Cumberland Plain alluvial terrain and Triassic carbonate-cemented deposits — contributing substantial dissolved minerals before Prospect treatment — at 168 mg/L and TDS 379.6 mg/L versus the predominantly Warragamba-sourced Redfern at 60 mg/L.

Zetland residents can expect moderate limescale build-up on taps and in kettles — descaling every four to six weeks is typical. Hot water systems benefit from periodic inspection. The elevated lead reading (0.004 mg/L) warrants briefly running the cold tap before use in Zetland's many new apartment buildings. Sydney Water provides water quality information at sydneywater.com.au, with all ADWG health standards consistently met. Zetland's Green Square urban renewal precinct and the rapidly growing City of Sydney southern residential corridor benefit from supply meeting all ADWG standards.