Toowoomba Tap Water Quality 2026: Free Chlorine (Not Chloramine), 47 Bores, and the Cressbrook Dam Project

10 min read

Toowoomba has one of the most unusual water supply profiles of any Queensland city. It is the only major QLD city not on the SEQ Water Grid, manages its own dams independently, draws 20-30% of its supply from 47 groundwater bores, and uses free chlorine rather than chloramine for disinfection. It is also the city that staged Australia’s most famous water referendum — the 2006 vote that rejected adding treated recycled sewage water to Cooby Dam by a decisive margin. Understanding Toowoomba’s supply means understanding why its water is fundamentally different to any coastal Queensland city.

Where Toowoomba’s water comes from

Toowoomba Regional Council manages the Bulk Water Supply Scheme, which serves the city of Toowoomba and surrounding towns across the Darling Downs. The primary surface water sources are three dams in the ranges northeast of the city: Cressbrook Dam (81,800 ML, the largest), Perseverance Dam (26,800 ML), and Cooby Dam (23,100 ML). These are supplemented by 47 groundwater bore stations that access subsurface aquifers and contribute approximately 20-30% of total supply — a groundwater reliance significantly higher than Brisbane, Sydney, or any coastal Australian capital.

Treatment occurs primarily at the Mt Kynoch Water Treatment Plant, with additional treatment at smaller plants at Pechey, Cressbrook, and Perseverance. A 38-kilometre pipeline from Wivenhoe Dam (operational since 2010) provides a backup source for the Cressbrook system, providing drought security when local dam levels fall critically low. Water is delivered via more than 370 km of pipelines, 18 reservoirs, and 17 pump stations.

The groundwater contribution is significant for water quality. Bore water typically has higher mineral content than surface water from dam catchments — the minerals accumulate as water moves through soil and rock. This means Toowoomba’s water hardness is typically higher and more variable than coastal QLD cities, with the specific characteristics depending on seasonal mix of dam water versus bore water in the distribution system.

The Cressbrook Dam safety project — 2024-2026

Since July 2024, Toowoomba Regional Council has been deliberately drawing primarily from Cressbrook Dam to lower its water level to approximately 70% before commencing a $270 million safety improvement project — Queensland’s largest local government-led dam safety project. The works involve widening the spillway and raising the dam crest to handle larger flood flows, as required by the Water Supply (Safety and Reliability) Act 2008. The project does not affect water supply to Toowoomba residents — treatment continues at Mt Kynoch WTP — but Perseverance Dam has been pumped to supplement supply during the Cressbrook drawdown period. Water quality is not impacted by the construction work, as the treatment plant sits downstream of the construction zone.

The 2006 recycled water referendum

Toowoomba holds a unique place in Australian water history. During the severe drought of the mid-2000s, Cooby Dam reached 8% capacity. Facing critical water shortage, the council proposed the “Toowoomba Water Futures” project: piping treated recycled wastewater (processed to drinking water standards) into Cooby Dam as a drought-resilient supply. On 29 July 2006, residents voted 62% to 38% against the proposal in a referendum that drew national attention.

The “no” vote became influential in Australian water policy debates. The technology proposed was not fundamentally different from what is now used in Singapore, parts of the US, and in Queensland’s Western Corridor Recycled Water Scheme (which indirectly supplements SEQ supplies during drought). Toowoomba’s water security instead came via the Wivenhoe pipeline, completed in 2010. The recycled water debate is historically relevant and recurs periodically in discussions about Queensland’s long-term water security.

Toowoomba water quality and what it means for filtration

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Frequently asked questions

What water filter works for Toowoomba tap water?

Because Toowoomba uses free chlorine (not chloramine), a standard NSF 42-certified activated carbon block filter such as the TAPP EcoPro works effectively. For fluoride removal or comprehensive filtration including TDS reduction, an RO system such as the EcoHero 5-stage is the appropriate choice.

Is Toowoomba water hard or soft?

Toowoomba water hardness varies depending on the current blend of dam and bore water. Bore contributions (20–30% of supply) add more minerals. Hardness typically ranges from 80–180 mg/L as CaCO3 depending on season — moderate by Australian standards.

What is the TDS of Toowoomba tap water?

Toowoomba TDS varies seasonally due to groundwater bore contributions. During high bore use periods, TDS can reach 200–300 mg/L. During high dam supply periods, TDS is typically lower, around 80–120 mg/L. Toowoomba Regional Council publishes annual water quality data.

Does Toowoomba tap water have fluoride?

Yes. Fluoride is added to Toowoomba water per Queensland Health’s Water Fluoridation Policy, targeting 0.7–1.0 mg/L. This is consistent with NHMRC recommendations for dental health.

Can I drink Toowoomba tap water without filtering?

Yes. Toowoomba Regional Council operates the supply to ADWG standards and all health parameters are met. Filtration is a personal preference choice for taste or to address bore-water mineral content — not a health requirement.

Is Toowoomba tap water safe to drink?

Yes. Toowoomba Regional Council manages the water supply from Cressbrook, Cooby, and Perseverance Dams plus 47 groundwater bores, treated at Mt Kynoch Water Treatment Plant. The supply meets Australian Drinking Water Guidelines and is safe to drink without filtration.

Does Toowoomba water have chloramine?

No. Unlike Brisbane, Gold Coast, and Ipswich which all use chloramine on the SEQ Water Grid, Toowoomba uses free chlorine for disinfection. This means standard activated carbon filters are effective — you do not need catalytic carbon. Toowoomba is the only major QLD city with free chlorine disinfection.

What was the Toowoomba recycled water referendum?

On 29 July 2006, during severe drought conditions with Cooby Dam at 8% capacity, Toowoomba residents voted 62% to 38% against a council proposal to add treated recycled wastewater (purified to drinking water standard) into Cooby Dam. The referendum attracted national attention and influenced Australian water policy debates. Water security was instead achieved via the Wivenhoe pipeline, completed in 2010.