2019 – Encounter Bay (South Australia) E.coli
14/3/19: Encounter Bay (South Australia) 1 sample E.coli 1 cfu/100mL
“Coliforms are Gram-negative, non-spore-forming, rod-shaped bacteria that are capable of aerobic and facultative anaerobic growth in the presence of bile salts or other surface active agents with similar growth-inhibiting properties. They are found in large numbers in the faeces of humans and other warm-blooded animals, but many species also occur in the environment.
Thermotolerant coliforms are a sub-group of coliforms that are able to grow at 44.5 ± 0.2°C. E. coli is the most common thermotolerant coliform present in faeces and is regarded as the most specific indicator of recent faecal contamination because generally it is not capable of growth in the environment. In contrast, some other thermotolerant coliforms (including strains of Klebsiella, Citrobacter and Enterobacter) are able to grow in the environment and their presence is not necessarily related to faecal contamination. While tests for thermotolerant coliforms can be simpler than for E. coli, E. coli is considered a superior indicator for detecting faecal contamination…” ADWG 2011
Encounter Bay (South Australia)
Breaches to Australian Drinking Water Guidelines Levels Only
18/12/2008 Encounter Bay Pollard Court Trihalomethanes – Total 262 ug/L
15/01/2009 Encounter Bay Pollard Court Trihalomethanes – Total 261 ug/L
12/02/2009 Encounter Bay Pollard Court Trihalomethanes – Total 265 ug/L
12/03/2009 Encounter Bay Pollard Court Trihalomethanes – Total 291 ug/L
17/12/2009 Encounter Bay Pollard Court Trihalomethanes – Total 286 ug/L
14/01/2010 Encounter Bay Pollard Court Trihalomethanes – Total 280 ug/L
11/02/2010 Encounter Bay Pollard Court Trihalomethanes – Total 273 ug/L
11/03/2010 Encounter Bay Pollard Court Trihalomethanes – Total 261 ug/L
8/04/2010 Encounter Bay Pollard Court Trihalomethanes – Total 285 ug/L
6/05/2010 Encounter Bay Pollard Court Trihalomethanes – Total 256 ug/L
23/09/2010 Encounter Bay Pollard Court Trihalomethanes – Total 258 ug/L
18/11/2010 Encounter Bay Pollard Court Trihalomethanes – Total 259 ug/L
16/12/2010 Encounter Bay Pollard Court Trihalomethanes – Total 259 ug/L
13/01/2011 Encounter Bay Pollard Court Trihalomethanes – Total 268 ug/L
10/02/2011 Encounter Bay Pollard Court Trihalomethanes – Total 263 ug/L
12/01/2012 Encounter Bay Pollard Court Trihalomethanes – Total 272 ug/L
3/05/2012 Encounter Bay Pollard Court Trihalomethanes – Total 256 ug/L
9/05/2013 Encounter Bay Pollard Court Trihalomethanes – Total 252 ug/L
18/03/2014 Encounter Bay Pollard Court Trihalomethanes – Total 275 ug/L
12/06/2014 Encounter Bay Pollard Court Trihalomethanes – Total 276 ug/L
3/09/2015 Encounter Bay Pollard Court Trihalomethanes – Total 262 ug/L
21/12/2015 Encounter Bay Pollard Court Trihalomethanes – Total 279 ug/L
12/05/2016 Encounter Bay Pollard Court Trihalomethanes – Total 273 ug/L
16/02/2017 Encounter Bay Pollard Court Trihalomethanes – Total 290 ug/L
16/03/2017 Encounter Bay Pollard Court Trihalomethanes – Total 282 ug/L
13/04/2017 Encounter Bay Pollard Court Trihalomethanes – Total 268 ug/L
8/06/2017 Encounter Bay Pollard Court Trihalomethanes – Total 260 ug/L
6-Jul-17 Encounter Bay Trihalomethanes – Total 255 µg/L
7-Sep-17 Encounter Bay Trihalomethanes – Total 262 µg/L
9-Nov-17 Encounter Bay Trihalomethanes – Total 270 µg/L
18-Jan-18 Encounter Bay Trihalomethanes – Total 287 µg/L
15-Feb-18 Encounter Bay Trihalomethanes – Total 265 µg/L
19-Apr-18 Encounter Bay Trihalomethanes – Total 271 µg/L
19/07/2019 Encounter Bay Trihalomethanes – 257 ug/l
16/08/2018 Encounter Bay Trihalomethanes – 294 ug/l
15/11/2018 Encounter Bay Trihalomethanes – 291 ug/l
17/01/2019 Encounter Bay Trihalomethanes – 260 ug/l
2018/19: Encounter Bay (South Australia) Trihalomethanes 294ug/L (max). 243.9ug/L (av. 2018/19)
16/1/20: Encounter Bay (South Australia) Trihalomethanes 258ug/L (max). 208.5mg/L (av. 2019/20)
10/6/21: Encounter Bay (South Australia) Trihalomethanes 253ug/L
9/9/21: Encounter Bay Trihalomethanes 253ug/L (max) 170.7ug/L (av. 2021/22)
Trihalomethanes Australian Guideline Level 250μg/L (0.25mg/L)
Why and how are THMs formed?
“When chlorine is added to water with organic material, such as algae, river weeds, and decaying leaves, THMs are formed. Residual chlorine molecules react with this harmless organic material to form a group of chlorinated chemical compounds, THMs. They are tasteless and odourless, but harmful and potentially toxic. The quantity of by-products formed is determined by several factors, such as the amount and type of organic material present in water, temperature, pH, chlorine dosage, contact time available for chlorine, and bromide concentration in the water. The organic matter in water mainly consists of a) humic substance, which is the organic portion of soil that remains after prolonged microbial decomposition formed by the decay of leaves, wood, and other vegetable matter; and b) fulvic acid, which is a water soluble substance of low molecular weight that is derived from humus”. Source: https://water.epa.gov/drink/contaminants/index.cfm
Encounter Bay (South Australia) – Bromodichloromethane
2018/19: Encounter Bay (South Australia) Bromodichloromethane 99ug/L (max), 81.5ug/L (av.)
16/1/20: Encounter Bay (South Australia) Bromodichloromethane 88ug/L (max). 69.7ug/L (av.)
9/7/20: Encounter Bay (South Australia) Bromodichloromethane 66ug/L
13/8/20: Encounter Bay (South Australia) Bromodichloromethane 64ug/L
10/9/20: Encounter Bay (South Australia) Bromodichloromethane 71ug/L
15/10/20: Encounter Bay (South Australia) Bromodichloromethane 79ug/L
12/11/20: Encounter Bay (South Australia) Bromodichloromethane 63ug/L
10/12/20: Encounter Bay (South Australia) Bromodichloromethane 76ug/L
14/1/21: Encounter Bay (South Australia) Bromodichloromethane 79ug/L
11/2/21: Encounter Bay (South Australia) Bromodichloromethane 71ug/L
11/3/21: Encounter Bay (South Australia) Bromodichloromethane 71ug/L
15/4/21: Encounter Bay (South Australia) Bromodichloromethane 69ug/L
15/4/21: Encounter Bay (South Australia) Bromodichloromethane 70ug/L
10/6/21: Encounter Bay (South Australia) Bromodichloromethane 85ug/L
14/10/21: Encounter Bay (South Australia) Bromodichloromethane 88ug/L (max), 55.17ug/L (av. 2021/22)
WHO Guideline level BDCM: 60ug/L (Australian Guideline for BDCM is included in the combined total of BDCM, Chloroform, Dibromochloromethane and Bromoform. THM guideline is 250ug/L)
“Carcinogenicity : Bromodichloromethane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Cancer Studies in Experimental Animals: Oral exposure to bromodichloromethane caused tumors at several different tissue sites in mice and rats. Administration of bromodichloromethane by stomach tube caused benign and malignant kidney tumors (tubular-cell adenoma and adenocarcinoma) in male mice and in rats of both sexes, benign and
malignant liver tumors (hepatocellular adenoma and carcinoma) in female mice, and benign and malignant colon tumors (adenomatous polyps and adenocarcinoma) in rats of both sexes (NTP 1987, ATSDR 1989, IARC 1991, 1999).
Since bromodichloromethane was listed in the Sixth Annual Report on Carcinogens, additional studies in rats have been identified. Administration of bromodichloromethane in the drinking water increased the combined incidence of benign and malignant liver tumors (hepatocellular adenoma or carcinoma) in males (George et al. 2002) and caused benign liver tumors (hepatocellular adenoma) in females (Tumasonis et al. 1987).
Cancer Studies in Humans
The data available from epidemiological studies are inadequate to evaluate the relationship between human cancer and exposure specifically to bromodichloromethane. Several epidemiological studies indicated a possible association between ingestion of chlorinated drinking water (which typically contains bromodichloromethane) and increased risk of
cancer in humans, but these studies could not provide information on whether any observed effects were due to bromodichloromethane or to one or more of the hundreds of other disinfection by-products also present in chlorinated water (ATSDR 1989).” (1)
Encounter Bay (South Australia) – Chloral Hydrate
18/12/08 Encounter Bay Chloral Hydrate 26.5ug/L
27/8/09 Encounter Bay Chloral Hydrate 23.6ug/L
24/9/09 Encounter Bay Chloral Hydrate 25.2ug/L
22/10/09 Encounter Bay Chloral Hydrate 28.3ug/L
19/11/09 Encounter Bay Chloral Hydrate 25.4ug/L
17/12/09 Encounter Bay Chloral Hydrate 29ug/L
14/1/10 Encounter Bay Chloral Hydrate 29.9ug/L
11/2/10 Encounter Bay Chloral Hydrate 24.5ug/L
3/6/10 Encounter Bay Chloral Hydrate 20.4ug/L
1/7/10 Encounter Bay Chloral Hydrate 27ug/L
29/7/10 Encounter Bay Chloral Hydrate 24.4ug/L
26/8/10 Encounter Bay Chloral Hydrate 27ug/L
23/9/10 Encounter Bay Chloral Hydrate 26.4ug/L
19/10/10 Encounter Bay Chloral Hydrate 31.9ug/L
18/11/10 Encounter Bay Chloral Hydrate 31.1ug/L
13/1/11 Encounter Bay Chloral Hydrate 26.2ug/L
25/8/11 Encounter Bay Chloral Hydrate 22.2ug/L
23/9/11 Encounter Bay Chloral Hydrate 22.7ug/L
17/11/11 Encounter Bay Chloral Hydrate 28ug/L
15/12/11 Encounter Bay Chloral Hydrate 27ug/L
Chloral hydrate is a disinfection by-product, arising from chlorination of water containing naturally occurring organic material (NOM). Chloral hydrate is a sedative and hypnotic drug. Long-term use of chloral hydrate is associated with a rapid development of tolerance to its effects and possible addiction as well as adverse effects including rashes, gastric
discomfort and severe renal, cardiac and hepatic failure.
2004 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.02mg/L
2011 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.1mg/L