AlburyCity has two water supply systems; reticulated potable (treated) water and raw (untreated) water.
Potable (treated) water system
The potable water scheme pumps water from the Murray River via one of three pump stations on the river to the Water Filtration Plant in East Albury. The location of the stations on the river ensures that pumps can draw the best-quality water available at any particular time.
Once treated, the potable water is pumped by one or more of the 16 distribution pumping stations to 35 service reservoirs scattered throughout the City. From these reservoirs the water gravitates to the 24,000 plus Albury customers through the reticulation system (22,500 of these customers are residential customers).
There is approximately 540kms of water mains of varying diameter ranging from 75mm diameter to 750mm. To maintain the treated water quality there are also six chlorine booster stations throughout the water reticulation system.
Albury has a total licensed allocation of 13,025 megalitres (one megalitre equals 1 million litres). A typical winter’s day consumption is around 15ML while in the summer months the average consumption is around 40ML. The highest recorded day’s consumption was 76.51ML and this occurred on 21 January 1997.
Raw (untreated) water system
We supply raw (untreated) water to a number of big businesses, including Norske Skog paper mill at Ettamogah, Overall Forge (a foundry at Ettamogah), Thurgoona Golf Club, Thurgoona Public School, Albury Wodonga Equestrian Centre and a number of residences at Ettamogah.
The scheme consists of a pump station on the Murray River, approximately 13.5kms of pumping main ranging in diameter from 500mm to 900mm, a booster pump station at Corrys Road Thurgoona, a 2ML rubber-lined open balance tank at Corrys Road and a 2.1ML reinforced concrete balance tank at One Tree Hill Reservoir. Associated with the raw water scheme is a 15.1km long return pipeline that allows the paper mill to return treated water to the Murray River.
Our treatment process
AlburyCity, along with all other Local Water Utilities (LWUs) in NSW are required to have a potable water system that delivers treated water that complies with the Australian Drinking Water Guidelines (ADWG) and the NSW Health Act.
LWUs are also regulated by the water section of the NSW Department of Primary Industries (DPI – Water) and also require an EPA licence.
Albury’s Water Treatment Plants
AlburyCity has two Water Filtration Plants (WFPs), both on the same site, located in Water Works and Boundary Roads East Albury. Plant ‘A’ (WFP ‘A’) was constructed in 1980 and Plant ‘B’ (WFP ‘B’) was constructed in 1990.
Both plants are fully automated and operate 24 hours a day, 7 days a week. Each can process 70 megalitres of water per day - the equivalent of 28 Olympic-sized swimming pools.
Both plants use the ‘direct filtration’ process although WFP ‘B’ is soon to be converted to the dissolved air flotation filtration process which will increase its capacity to around 90 megalitres per day.
The treatment process
Raw (untreated) water is pumped directly from the Murray River to the Water Filtration Plant.
When the raw water arrives at the plant, it goes through the various treatment processes. Part of the process sees the water passing through a filter medium consisting of layers of gravel and sand, and topped with a layer of antracite (a hard filter coal). This process removes the dirt particles in the raw water.
The filters must be cleaned every eight to 24 hours depending upon the quality of the raw water. To clean the filters, clean water is pumped back through the filters to remove the accumulated dirt. The backwash water is then discharged to one of the four sludge lagoons, where the dirt settles out. The return water is then pumped back to the filtration plant and mixed with the incoming raw water. Approximately every 12 months, the lagoon is allowed to dry out and the dried sludge is either disposed of off-site or spread over the facility grounds as topsoil.
Part of the treatment process also sees specific chemicals being added to improve the treatment process and/or improve the water quality. These chemicals include:
- Alum (in the form of Aluminium Sulphate) and polyelectrolyte (a non-ionic polymer) are added to assist with the coagulation and flocculation process. Essentially, these chemicals cause the dirt particles to stick together so that it is easier to filter out the dirt
- Lime is added for pH correction, i.e. to control the acidic level that naturally occurs in water
- Chlorine (in the form of a gas) is added/used as a disinfectant to kill any microorganisms in the water
- Fluoride (in the form of Sodium silica fluoride [Na2SiF6] ) is added to improve the health of teeth (and is a requirement of NSW Health)
- Powdered Activated Carbon (PAC) is added to remove algal toxins and control the earthy smell of the water by reducing the levels of methylisoborneol (commonly known as MIB) and geosmin. This process usually only occurs in the months of February and March.
The addition of all of these chemicals and all treatment processes are closely monitored and testing occurs regularly on a daily basis. As part of the automated process of producing treated water the plant has the ability to shut-down if certain water standards or quality limits are not met.
Water Testing and Certification
Water samples are regularly taken from the Water Filtration Plant and the reticulation system for testing to ensure they meet Australian Drinking Water Guidelines and specific NSW Health requirements.
Around 35 tests per day are performed on water being treated at the plant and approximately 45 tests per week are carried out on water taken from the reticulation system. In addition, AlburyCity Health Officers take an average of five samples per week from the reticulation system for testing on behalf of NSW Health.
The plant uses specialised online analysers which test some of the samples automatically on-site, and the results are used to assist with maintaining the operations of the Water Filtration Plant and the reticulation system.
The tests measure factors such as:
- chlorine level
- pH level (which indicates water acidity/alkalinity)
- fluoride level
- turbidity (water cloudiness)
- coliforms (which indicates the level of bacteria in the water)
- E-coli presence (E-coli bacteria can cause stomach cramps, vomiting and diarrhoea).
AlburyCity records results of all of these tests to meet requirements for accreditation for operation of a Water Filtration Plant and reticulation system.
Once the treatment process is complete and the water is ready for drinking, it is stored in four storage tanks at the site before being distributed to users through the reticulation system.
Regulatory control and performance reporting
Our water supply system is regulated by the NSW Department of Primary Industries Water Section (DPI-Water).
The operations of the water supply system are reported annually, with around 250 responses being provided. DPI-Water collates all of these results and these are reported on and benchmarked against the other 107 local water utilities throughout NSW.
Because we have more than 20,000 customers, our results are also nationally benchmarked.
We also have an Environment Protection Authority (EPA) licence for our Water Filtration Plant and this is reported on annually.