Water
The water supply system in Forbes supplies potable water to Forbes, Calarie and Daroobalgie as well as other villages of neighboring shires, including Gunningbland, Bogan Gate, Trundle, Tullamore and Tottenham. Forbes obtains its raw water either from the Lachlan River or one of three groundwater bores (constructed along the New Grenfell Road and the Cowra Road, approximately 10 km south east of Forbes). The bores provide a back-up water supply in the event of an extended drought threatening the river supply. Water is treated by a conventional sand filtration water treatment plant (capacity - 26 ML/d) and reticulated to the town area via four service reservoirs (capacity – 30ML) and 130 kms of water mains. Council has a 4,700ML high security river allocation, and currently uses around 2,500ML annually.
The water treatment process includes flocculation, sedimentation, filtration, chlorination and fluoridation. The plant was constructed in 1940’s with a major amplification in the mid 1960’s and other ongoing improvements over the years. Due to the age of the plant, Council is beginning a process to investigate options for the plants renewal or replacement.
The water supply has monthly chemical analyses to ensure water meets the Australian drinking water guidelines and 64 microbiological tests conducted over the year, as well the many operational tests conducted by our water plant operators.
Council also manages a reticulated raw water supply to the village of Ootha, as well as a raw water system to irrigate the parks and ovals around Lake Forbes.
Complaints Line: 02 6850 2300
Drinking Water Monitoring Report Forbes Shire Council 2024
In 2024, Forbes Shire Council performed routine drinking water sampling and testing to monitor the quality of drinking water. The results were submitted to the NSW Drinking Water Database.
Compliance is determined against the Australian Drinking Water Guidelines (2011) guideline values for E. coli, physical and chemical characteristics of drinking water.
The Forbes Shire Council supply system achieved compliance of 95% for physical, 100% for chemical, and 100% for microbiological samples.
Data presented below are sourced through the performance comparison report and results reports from the NSW Health Drinking Water Database.
Table 1. Forbes WTP Water Quality Compliance
|
Sample Type
|
Sample Count
|
Number of Characteristics
|
Number of Non‑CompliantSamples
|
Compliance (%)
|
|
Physical
|
12
|
60
|
3
|
95
|
|
Chemical
|
12
|
228
|
0
|
100
|
|
Microbiological
|
64
|
|
0
|
100
|
Water Quality
Routine Drinking Water Monitoring Characteristics
Table 2. Forbes WTP Chronic health-related Chemical Water Quality Data
|
Characteristic
|
Guideline Value
|
Mean
|
Maximum
|
Sample count
|
Meeting Guideline Value (%)
|
|
Antimony
|
0.003
|
0.0001
|
0.0001
|
12
|
100
|
|
Arsenic
|
0.01
|
0.001
|
0.001
|
12
|
100
|
|
Barium
|
2
|
0.0398
|
0.0632
|
12
|
100
|
|
Boron
|
4
|
0.0117
|
0.0177
|
12
|
100
|
|
Cadmium
|
0.002
|
0.0001
|
0.00005
|
12
|
100
|
|
Chromium
|
0.05
|
0.0005
|
0.0005
|
12
|
100
|
|
Fluoride
|
1.5
|
0.9708
|
1.11
|
12
|
100
|
|
Iodine
|
0.5
|
0.0283
|
0.04
|
12
|
100
|
|
Lead
|
0.01
|
0.0012
|
0.0043
|
12
|
100
|
|
Manganese
|
0.5
|
0.0008
|
0.0071
|
12
|
100
|
|
Mercury
|
0.001
|
0.0004
|
0.0004
|
12
|
100
|
|
Molybdenum
|
0.05
|
0.0003
|
0.0004
|
12
|
100
|
|
Nickel
|
0.02
|
0.0005
|
0.0008
|
12
|
100
|
|
pH
|
6.5 - 8.5
|
7.5417
|
7.9
|
12
|
100
|
|
Selenium
|
0.01
|
0.0035
|
0.0035
|
12
|
100
|
|
Silver
|
0.1
|
0.0001
|
0.0001
|
12
|
100
|
|
Uranium
|
0.02
|
0.0001
|
0.0001
|
12
|
100
|
Chronic health-related chemical characteristics are inorganic chemicals that might be present in water and can pose a risk to health with prolonged exposure. The Guideline values for these materials are usually set to be protective over a lifetime of exposure. Single results above a Guideline values are unlikely to pose a risk to health; compliance is based on analysing long term trends.
Table 2a. Forbes WTP Acute health-related Chemical Water Quality Data
|
Characteristic
|
Guideline Value
|
Mean
|
Maximum
|
Sample count
|
Meeting Guideline Value (%)
|
|
Copper
|
2
|
0.1238
|
0.609
|
12
|
100
|
|
Nitrate
|
50
|
1.4167
|
2
|
12
|
100
|
|
Nitrite
|
3
|
0.05
|
0.05
|
12
|
100
|
Acute health-related chemical characteristics are inorganic chemicals that can pose a health risk based on a small number of exposures. High concentrations of copper can cause vomiting. High concentrations of nitrite or nitrate can be risky for bottle-fed babies. The Guideline values for these characteristics have been set to protect people from short-term exposure.
Table 2b. Forbes WTP Physical and Selected Aesthetic Chemical Water Quality Data
|
Characteristic
|
Guideline Value
|
Mean
|
Maximum
|
Sample count
|
Meeting Guideline Value (%)
|
|
Iron
|
0.3
|
0.005
|
0.005
|
12
|
100
|
|
Sodium
|
180
|
39.1667
|
64
|
12
|
100
|
|
Total dissolved solids
|
10000
|
239.1667
|
465
|
12
|
100
|
|
Total hardness
|
200
|
158.0333
|
279.4
|
12
|
75
|
|
True Colour
|
15
|
1.3333
|
3
|
12
|
100
|
|
Turbidity
|
5
|
0.2708
|
1.2
|
12
|
100
|
Physical and aesthetic chemical characteristics change the way that water appears; its taste, smell, look and feel. These characteristics do not have health guideline values but do affect how people feel about their drinking water.
Table 3. Forbes WTP Microbiological Water Quality Data
|
Characteristic
|
Guideline Value
|
Mean
|
Maximum
|
Sample count
|
Meeting Guideline Value (%)
|
|
E. coli
|
0
|
0
|
0
|
64
|
100
|
|
Free Chlorine
|
0.2 - 5
|
1.885
|
3.36
|
64
|
85.94
|
|
Total Chlorine
|
5
|
2.2108
|
3.69
|
64
|
100
|
Escherichia coli, a bacteria found in the gut of many backboned animals, is an indicator that there has been recent contamination with faeces in a drinking water supply. Chlorine is used widely to kill disease-causing organisms in drinking water. A reasonable residual concentration in the supply provides ongoing protection all the way to customer taps, and gives some indication that filtration is working well and the distribution system is has not been compromised.
Other Monitoring
Per- and Poly-fluorinated alkyl substances (PFAS) testing
|
Characteristic
|
Guideline Value
|
Mean
|
Maximum
|
Meeting Guideline Value (%)
|
|
Sum of perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS)
|
<70 ng/L
|
-
|
<0.2 ng/L
|
100
|
|
Perfluorooctanoic acid (PFOA)
|
<560 ng/L
|
-
|
<0.1 ng/L
|
100
|
PFAS are a class of chemicals that have been developed for fire-fighting, stain and water resistance and other uses. They can pose a risk to health with prolonged exposure. The Guideline values for these materials are set to be protective over a lifetime of exposure.