2013/14 Raglan * E.coli 280orgs / 100 mL max 29.2% samples no E.coli
2014/15 Raglan * Ecoli 110orgs / 100 mL max 25% samples no E.coli
2015/16 Raglan * E.coli 23orgs / 100 mL 69max 26.1%samples no E.coli
2016/17 E.coli Raglan 190orgs / 100 mL max 16.7% samples no E.coli
2018/19 E.coli Raglan 96orgs / 100 mL
2019/20 E.coli Raglan 120orgs/100 mL max
“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
Raglan – Victoria – Turbidity
2008/09: Raglan (Victoria) – Turbidity 18 NTU
2010/11: Raglan (Victoria) – Turbidity 17 NTU
2011/12: Raglan Turbidity 7.5NTU
2012/13: Raglan Turbidity 6.6NTU
2016/17Raglan Turbidity 5.1NTU
2017/18: Raglan (Victoria) – Turbidity 13 NTU (max)
2019/20: Raglan (Victoria) – Turbidity 7.9 NTU (max)
Chlorine-resistant pathogen reduction: Where filtration alone is used as the water treatment
process to address identified risks from Cryptosporidium and Giardia, it is essential
that filtration is optimised and consequently the target for the turbidity of water leaving
individual filters should be less than 0.2 NTU, and should not exceed 0.5 NTU at any time
Disinfection: A turbidity of less than 1 NTU is desirable at the time of disinfection with
chlorine unless a higher value can be validated in a specific context.
Aesthetic: Based on aesthetic considerations, the turbidity should not exceed 5 NTU at the
consumer’s tap.
Raglan (Victoria) – Colour
2008/09: Raglan (Victoria) – Colour 180 HU
2009/10: Raglan (Victoria) – Colour 150 HU
2010/11: Raglan (Victoria) – Colour 190 HU
2011/12 Raglan Colour 140HU
2012/13 Raglan Colour 110HU
2013/14 Raglan Colour 190HU
2014/15 Raglan Colour 110HU
2015/16 Raglan Colour 180HU
2016/17Raglan Colour 190HU
2017/18: Raglan (Victoria) – Colour 140 HU
2018/19: Raglan (Victoria) – Colour 60 HU (max), 24 HU (mean)
2020/21: Raglan (Victoria) – Colour 85HU (max), 45HU (mean)
Based on aesthetic considerations, true colour in drinking water should not exceed 15 HU.
“… Colour is generally related to organic content, and while colour derived from natural sources such as humic and fulvic acids is not a health consideration, chlorination of such water can produce a variety of chlorinated organic compounds as by-products (see Section 6.3.2 on disinfection by-products). If the colour is high at the time of disinfection, then the water should be checked for disinfection by-products. It should be noted, however, that low colour at the time of disinfection does not necessarily mean that the concentration of disinfection by-products will be low…
Raglan – Victoria – Iron
2008/09: Raglan (Victoria) – Iron 0.62mg/L
2009/10: Raglan (Victoria) – Iron 0.38mg/L
2010/11: Raglan (Victoria) – Iron 1mg/L
2011/12 Raglan Iron 0.48mg/L
2014/15: Raglan Iron 0.76mg/L
2016/17: Raglan Iron 0.48mg/L
2017/18: Raglan (Victoria) – Iron 0.57mg/L
2019/20: Raglan (Victoria) – Iron 0.58mg/L (max)
Based on aesthetic considerations (precipitation of iron from solution and taste),
the concentration of iron in drinking water should not exceed 0.3 mg/L.
No health-based guideline value has been set for iron.
Iron has a taste threshold of about 0.3 mg/L in water, and becomes objectionable above 3 mg/L. High iron concentrations give water an undesirable rust-brown appearance and can cause staining of laundry and plumbing fittings, fouling of ion-exchange softeners, and blockages in irrigation systems. Growths of iron bacteria, which concentrate iron, may cause taste and odour problems and lead to pipe restrictions, blockages and corrosion. ADWG 2011