Riverwood Water Hardness & Quality Report (2026)

Sydney Water provides the metropolitan area of Greater Sydney, including Riverwood (postcode 2210), with drinking water for over 5 million residents. The supply is drawn from a network of 11 dams, with Warragamba Dam being the largest, alongside Woronora Dam, Nepean Dam, Avon Dam, and Cordeaux Dam. Major treatment facilities like the Prospect Water Filtration Plant, North Richmond, and Woronora employ multi-stage processes including coagulation, flocculation, sedimentation, filtration, and chloramination for disinfection. The extensive Greater Sydney catchment, covering 16,000 km² of bushland, primarily focuses on the Warragamba Dam catchment in the Blue Mountains and Southern Highlands.

The water's journey begins in a landscape dominated by Triassic-age Hawkesbury Sandstone and shale formations, with very few limestone or dolomite outcrops. This quartz-rich geology is the key reason for the naturally soft water profile found in Riverwood. Unlike regions with carbonate rocks, the sandstone releases very few calcium and magnesium ions into the water as it infiltrates. The limited contribution from groundwater further helps maintain this soft water character, making it a distinct feature of the Greater Sydney supply.

Because the water supplied to Riverwood is soft, homeowners generally won't face issues with limescale buildup in plumbing, kettles, or washing machines. You can expect extended appliance life and may find you need less soap and detergent for cleaning. While a water softener isn't necessary, it's worth noting that very soft water can sometimes be slightly aggressive towards metals in hot water systems, so occasional checks for corrosion might be prudent. Regular descaling of appliances isn't typically required. Sydney Water consistently reports excellent water quality, with pH levels usually between 7.2 and 7.8, and full compliance with lead and copper guidelines.