Mentone Water Hardness & Quality Report (2026)

South East Water provides drinking water to Mentone, Victoria, Australia, serving areas within Melbourne's southeast suburbs, including the Kingston and Bayside local government areas. The supply largely comes from Melbourne Water's integrated system, drawing from significant reservoirs like Thomson, Upper Yarra, Maroondah, and Sugarloaf. Water is treated at facilities such as the Cardinia and Thomastown Water Treatment Plants before being distributed through a vast network. Mentone receives a blend of this metropolitan supply, sometimes supplemented by the Victorian Desalination Plant during periods of high demand.

This water originates from the protected Yarra and Thomson River watersheds, located in Victoria's Central Highlands. These areas cover more than 1,900 square kilometers of forested catchments. The underlying geology is characterized by Paleozoic sedimentary basins featuring quartz-rich sandstones, shales, and granitic intrusions dating back to the Silurian-Devonian period. Crucially, there are no extensive layers of carbonate rock. Consequently, the water is very soft, with minimal mineral content, as surface waters collect very little dissolved calcium and magnesium from the siliceous soils and bedrock during rainfall and river flow.

Because the water is very soft, you'll find virtually no scale buildup on fixtures and appliances, so there's no risk to items like kettles or hot water systems. Soap will lather easily, meaning you might use less, and you won't need to adjust detergent levels. Maintenance related to water hardness is minimal. While very soft water can slightly increase the risk of corrosion in older galvanized pipes, modern plumbing made of copper or plastic materials is unaffected. Installing a water softener is unnecessary and could remove beneficial minerals. The water quality consistently exceeds the Australian Drinking Water Guidelines.