Marrickville Water Hardness & Quality Report (2026)

Sydney Water supplies the inner-west Sydney suburb of Marrickville, NSW, Australia. The utility draws from the Nepean River, Shoalhaven River, and Hawkesbury River systems, supplemented by groundwater from the Sydney Basin. Water travels from watersheds in the Blue Mountains and Southern Highlands to Sydney Water's treatment plants before distribution via the metropolitan network. Marrickville's water originates from sources that flow over sandstone, shale, and coal seams within the Sydney Basin.

These Sydney Basin geological formations, primarily Triassic and Permian sandstone and shale, are siliciclastic. This means they contain minimal carbonate minerals like limestone or dolomite. As a result, very little calcium and magnesium dissolve into the water as it travels through these rock types and aquifers. This natural process is why the water supply across Greater Sydney, including Marrickville, is characterised by its soft nature and low mineral content.

Because the water is soft, you'll notice less limescale buildup on your taps, appliances, and inside your pipes. Things like kettles and dishwashers won't need frequent descaling, and soap will lather up easily. While a water softener isn't typically needed, some Marrickville residents opt for one to address potential issues from older household plumbing. Sydney Water reports that aging pipes or tanks could introduce lead, copper, or bacteria after the water leaves their treatment facilities.