Southern River Water Hardness & Quality Report (2026)

Southern River's drinking water is supplied by the Water Corporation via the Integrated Water Supply Scheme (IWSS), incorporating a balanced blend of desalinated supply and Gnangara Mound groundwater for the City of Gosnells LGA outer south-eastern Perth distribution in Western Australia. Water hardness in Southern River is measured at 120.5 mg/L — classified as moderately hard — within the Australian Drinking Water Guidelines (ADWG) aesthetic guideline of 200 mg/L published by NHMRC. Southern River — a large outer south-eastern Perth residential growth suburb in the Gosnells LGA, known for the Gosnells Botanical Garden, the Southern River Country Club, and the extensive residential estate development in the Perth south-eastern urban growth corridor — receives moderately hard supply, substantially softer than the harder Forrestfield (238 mg/L, Kalamunda) and Armadale (166.5 mg/L) in nearby eastern Perth areas.

Southern River's moderately hard supply reflects a higher desalinated supply proportion moderating the Gnangara Mound groundwater hardness in the outer south-eastern Gosnells IWSS distribution. The proximity to the Kwinana and Binningup Seawater Desalination Plants and the IWSS southern distribution routing delivers a proportionally higher desalinated supply fraction to the Gosnells south-eastern corridor at 120.5 mg/L and TDS 272.6 mg/L, substantially softer than the groundwater-dominant outer eastern and outer northern Perth distribution zones.

Southern River residents face moderate limescale build-up on taps and in kettles — descaling every two to three months is typically adequate. Hot water systems benefit from periodic inspection. Solar hot water systems in WA's climate benefit from annual servicing. Under WA water restrictions, garden irrigation is limited to two days per week. The very low lead reading (0.001 mg/L) is excellent. The Water Corporation provides water quality information at watercorporation.com.au, with all ADWG health standards consistently met. Southern River's outer south-eastern Perth residential growth community benefits from a supply meeting all ADWG standards.