Water Quality

Water Quality and Water Leaks(PDF, 889KB)

Drinking Water Blue-Green Algae Management Plan(PDF, 596KB) 

Potable water is safe drinking water free of harmful concentrations of chemicals or pathogenic microorganisms.  The Australian Drinking Water Quality Guidelines (ADWQG) are used by Isaac Regional Council (Council) to provide safe, good quality drinking water. Council’s Drinking Water Quality Management Plan (DWQMP) is approved by the Department of Regional Development, Manufacturing and Water. 

As detailed in the Drinking Water Quality Management Plan (DWQMP), Council strictly follows various testing and monitoring regimes to ensure drinking water is always safe. Contaminated water may not look, taste, or smell different to safe drinking water. This is why monitoring and testing of water is so important. The Australian Drinking Water Quality Guidelines (ADWQG) are followed stringently by Council with implemented monitoring programs to ensure a safe drinking water supply and protect public health. Each year, we conduct over 10,000 tests at our eight (8) water treatment plants for more than 100 parameters. We perform daily operational testing and continuous online monitoring at our water treatment plants and many of our water storage tanks and dams.

In addition to this, compliance sampling, verification monitoring and analysis is also conducted by a National Association of Testing Authorities accredited Laboratory. 

Chlorine is added to drinking water to kill microorganisms (i.e. E. coli) that may be present. It is important that chlorine residual is maintained in the drinking water after leaving the plant to prevent microorganisms from regrowing in the water pipelines. Some people may detect this chlorine residual through smell or taste. The chlorine concentration is generally very low (less than 1 part per million) and can be reduced further by letting the water sit in the fridge in an open jug for a short period prior to consumption. 

Turbidity is caused by the presence of fine suspended matter such as clay and silt and can result in the water having a muddy or milky appearance. Turbidity reduction most commonly occurs via coagulation, clarification and filtration water treatment processes. Council monitors this with online systems and daily testing to ensure levels in our drinking water continues to meet the Australian Drinking Water Guidelines (ADWQG).

Water can become discoloured for a number of reasons, including the disturbance of sediments within the water mains. Our distribution systems are flushed routinely as part of our preventative maintenance program. Discoloured water can also arise due to the condition of private service pipes or internal plumbing, particularly in older properties.

If your water is discoloured, we suggest that you run at least two taps (such as your garden taps) for a few minutes until the water clears. If the water does not clear up within a reasonable amount of time, then we suggest that you call Council on 1300 ISAACS (1300 472 227) for assistance.

A milky or white appearance may indicate the presence of air in your water – similar to the air created by a tap with a diffuser fitted. This air is harmless and will usually settle out if left to stand in a jug or container. We suggest that you run at least two taps (such as your garden taps) for a few minutes until the water runs clear. If the water does not clear up within a reasonable amount of time, then we suggest that you call Council on 1300 ISAACS (1300 472 227) for assistance.

Some algae can produce taste, odour and toxic compounds. However, Council has treatment processes in place which prevents these from impacting on the quality of our drinking water. We also conduct algae monitoring throughout our drinking water catchments during the warmer months of the year when algae blooms are more common.

Blue or bluish-green staining is often an indicator of elevated copper levels and is often caused by age and corrosion in customers’ pipes. Council monitors for copper levels and has consistently low copper results in all systems. Advice on the condition of your property’s pipes should be sought from your plumber.

The quality of water in rainwater tanks is usually high in bacteria. Details on rainwater tanks and drinking water is available at the Department of Health and Aged Care website

Isaac Regional Council DWQMP Audit Report 2022(PDF, 8MB)

Isaac Regional Council Drinking Water Quality Management Plan(PDF, 36MB)

IRC-DWQMP-Annual-Report-2023-24_Redacted.pdf(PDF, 2MB)

Annual Report - Drinking Water Quality Management Plan (DWQMP) 2022-202(PDF, 8MB)3(PDF, 8MB)

IRC DWQMP 2021-22 Annual Report(PDF, 1014KB)

IRC DWQMP 2020-21 Annual Report(PDF, 1MB)

IRC DWQMP 2019-20 Annual Report(PDF, 1MB) 

SWIM-DNRME-KPI-23-24.pdf(PDF, 695KB)

(PDF, 574KB) SWIM-DNRME-KPI-22-23.pdf(PDF, 237KB)

SWIM DNRME KPI - 21-22(PDF, 574KB)