2013/20 – Googong Reservoir (Australian Capital Territory) – Cyanobacteria, Lead, Cryptosporidium

2013/20:  Googong Reservoir (Australian Capital Territory) – Cyanobacteria

03/07/13: High risk Cyanobacteria >2000 cells/mL or a total biovolume 0.5mm3/L
High risk cyanobacteria Anabaena and Anabaenopsis were detected at a sample point located upstream of the Googong Storage Reservoir. Googong WTP was not operating at the time of the detection.

23/12/13: Cyanobacteria >2000 cells/mL or a total biovolume 0.5mm3/L
High risk cyanobacteria Anabaena was detected at a sample point within the Googong Storage Reservoir at the surface and 3 m. Anabaena was also detected at a sample point located upstream of the reservoir. At the time of the detection Googong WTP was not operating.

11/4/14: Cyanobacteria >2000 cells/mL or a total biovolume 0.5mm3/L
High risk cyanobacteria Anabaena was detected at a sample point within the Googong Storage Reservoir at a depth of 9 m. At the time of the detection Googong WTP was not operating

7/8/14: Raw water in the storage reservoir. Cyanobacteria High risk cyanobacteria Anabaena was detected at a concentration of 2,697 cells/mL within the Googong storage reservoir, approximately 6 km upstream of the off take tower at a depth of 3 m. Googong WTP was online and water was being selectively abstracted from a depth of 15 m. In response to the detection Icon Water’s blue-green algae response plan was activated. Taste and odour monitoring was conducted on a daily basis at the WTP and the Powdered Activated Carbon (PAC) system was placed on standby. Sampling was increased to twice weekly until the bloom declined. No complaints were received for taste or odour during this period.

11/4/16: Raw water in a storage reservoir
High risk cyanobacteria, Anabaena, was detected at a concentration of 3,081 cells/mL in a surface water sample within the Googong storage reservoir, approximately 2.5 km upstream from the off take tower. Googong Water Treatment Plant was offline at the time of sampling. Water quality monitoring continued at the storage reservoir as per the routine monitoring program. No further action was required.

21/11/16: High risk cyanobacteria, Dolicospermum, was detected in two samples collected within the Googong reservoir. At the offtake tower site 4,352 cells/mL were recorded, whilst there were 2,752 cells/mL detected at a site approximately 2.5 km upstream of the offtake tower. Googong Water Treatment Plant was offline at the time of sampling. Water quality monitoring continued at the storage reservoir as per the routine monitoring program. No further action was required.

28/6/17: High risk cyanobacteria, Dolicospermum, was detected at concentrations of 3,128 cells/mL and 2,476 cells/mL in the surface samples at two sites. Each site is located at an inlet to the Googong reservoir and are upstream from the offtake tower. Googong Water Treatment Plant was offline at the time of sampling. Water quality monitoring continued at the storage reservoir as per the routine monitoring program. Data from the program was used to determine whether additional treatment would be utilised once the plant came online.

6/2/2019: Cyanobacteria High risk cyanobacteria, Dolicospermum, was detected at
concentrations of between 2000 and 3699 cells/mL in surface water samples in the Googong reservoir. At the time of sampling water was being abstracted and treated at GWTP and supplied to Queanbeyan and parts of the ACT.

26/3/20: High risk cyanobacteria, Dolicospermum and Microcystis was detected at notifiable levels in surface water samples in the Googong reservoir. At the time of sampling water was being abstracted and treated at GWTP and supplied to Queanbeyan and parts of the ACT.

22/4/20: High risk cyanobacteria, Dolicospermum was detected at a notifiable level in surface water samples in the Googong reservoir upstream of the inlet tower. At the time of sampling water was not being abstracted for supply.

28/5/20: High risk cyanobacteria, Microcystis, was detected at notifiable levels in surface water samples at the Bendora reservoir intake tower. At the time of sampling water was being abstracted and treated at SWTP and supplied to ACT and Queanbeyan.

Googong Foreshore (Australian Capital Territory) – Lead

15/12/14: Water within the distribution system at customer tap
Inorganic or organic chemicals with a health guideline value
Lead was detected above the ADWG in a tap at the Googong Foreshore. After further investigation it was suspected that the elevated lead concentration was from aged water within the service line that the sample was collected from. Icon Water continued to collect samples from the tap to monitor the water quality.

Googong Reservoir (ACT) – Crytposporidium

25/11/19: Cryptosporidium at a concentration of 0.05 oocysts/L was detected in a composite sample at Googong intake tower. At the time all other water quality parameters were found to be within specification and no Cryptosporidium was detected in the WTP raw water or final supply.

27/11/19: Cryptosporidium at a concentration of 0.018 oocysts/L was detected in the raw water entering Googong WTP. At the time all other water quality parameters were found to be within specification and no Cryptosporidium was detected in the final supply.

Cryptosporidium

“In recent years, Cryptosporidium has come to be regarded as one of the most important waterborne human pathogens in developed countries. Over 30 outbreaks associated with drinking water have beenreported in North America and Britain, with the largest infecting an estimated 403,000 people (Mackenzieet al. 1994). Recent research has led to improved methods for testing water for the presence of humaninfectious species, although such tests remain technically demanding and relatively expensive.

Cryptosporidium is an obligate parasite with a complex life cycle that involves intracellular development in the gut wall, with sexual and asexual reproduction. Thick-walled oocysts, shed in faeces are responsible for transmission. Concentrations of oocysts as high as 14,000 per litre in raw sewage and 5,800 per litre in surface water have been reported (Madore et al. 1987). Oocysts are robust and can survive for weeks to months in fresh water under cold conditions (King and Monis 2007).

There are a number of species of Cryptosporidium, with C. hominis and C. parvum identified as the main causes of disease (cryptosporidiosis) in humans. C. hominis appears to be confined to human hosts, while the C. parvum strains that infect humans also occur in cattle and sheep. C. parvum infection sare particularly common in young animals, and it has been reported that infected calves can excrete up to 10 billion oocysts in one day. Waterborne outbreaks of cryptosporidiosis have been attributed to inadequate or faulty treatment and contamination by human or livestock (particularly cattle) waste.

C. hominis and C. parvum can be distinguished from one another and from other Cryptosporidium species  by a number of genotyping methods. Infectivity tests using cell culture techniques have also been developed. Consumption of contaminated drinking water is only one of several mechanisms by which transmission (faecal-oral) can occur. Recreational waters, including swimming pools, are an important source of cryptosporidiosis and direct contact with a human carrier is also a common route of transmission.Transmission of Cryptosporidium can also occur by contact with infected farm animals, and occasionally through contaminated food.” ADWG 2011