Our drinking water is among the best in the world. We provide clean, safe and reliable drinking water to 5.6 million people every day.
Where your drinking water comes from
Most of the drinking water for Sydney, the Blue Mountains and the Illawarra starts as rain, captured and stored in lakes surrounded by native bushland in the Blue Mountains and the Southern Highlands.
WaterNSW supplies us with raw water from protected lakes and rivers, with around 80% of our water coming from Warragamba Dam.
We also source water from the ocean, which we turn into drinking water using the Sydney Desalination Plant. Desalinated water is especially valuable during droughts.
Lake Burragorang, Warragamba Dam
How we filter your water
Our 9 water filtration plants are operated by skilled teams dedicated to providing safe and reliable drinking water. We filter 100% of your water to ensure it's safe to drink straight from the tap. Every drop we supply meets the Australian Drinking Water Guidelines.
Water treatment steps
- Screening
We remove large debris, such as twigs and leaves, using fine mesh screens. - pH adjustment
We adjust the pH to support the filtration process. - Coagulation
We add a solution called a coagulant. This helps very small particles stick together to form larger clumps called floc. This makes them easier to filter out. - Filtration
We filter the water through tightly packed beds of sand and crushed coal to trap and remove the floc. We clean our filters several times a week. We also check their performance to maintain high water quality. - Final pH balance
We carefully rebalance the pH of the water. - Disinfection
We add small amounts of chlorine to protect the water from harmful pathogens.
The bonus of stronger teeth
NSW Health recommends adding small amounts of fluoride to drinking water to help prevent tooth decay. Our daily drinking water quality report includes how your water's fluoride levels compare with our limit of 1.5 milligrams per litre.
How we monitor quality
Our water quality monitoring program comprises 70 different analytical tests to confirm your drinking water is high quality and safe. These tests assess key water quality characteristics, including taste and odour, colour, microorganisms and chemical composition. Sydney Water Laboratory Services collects and tests samples taken from source to tap, including lakes and rivers, our water filtration plants, and at homes and businesses.
- See how our treatment systems are performing in our daily drinking water quality report.
- Find out what's in your water, including our Quarterly Drinking Water Quality Report.
How we set our standards
We have a Drinking Water Management System based on the Australian Drinking Water Guidelines. Our Drinking Water Management Plan outlines how we apply this framework across our entire area of operation. NSW Health reviews our annual monitoring program and provides expert public health advice. IPART conducts yearly audits under our Operating Licence. If a potential water quality issue is identified, we follow our Drinking Water Quality Event Management Plan, consult NSW Health and notify customers.