Dookie (Victoria) – Trichloroacetic Acid
11/9/24: Dookie (Victoria) Trichloroacetic Acid 0.14mg/L
GVW conducted a root cause analysis of the water treatment plant. Operators undertook a thorough investigation of raw water extraction and quality details, also interrogated disinfection dosing and trending. All sampling and field data results were also within specification on the day the sample was
taken. All processes and results were within expected parameters, and no immediate root cause was identifiable.
The distribution network Sample Point is located at the furthest point in the network away from the treatment plant, as well as located on a dead end main. GVW’s conclusion was that due to a combination of organics in the source water, reacting with the liquid sodium hypochlorite, and water age
all contributed to this high result for trichloroacetic acid. GVW undertook flushing of the water main and resampling for chloroacetic acids were undertaken and no detections found.
Australian Guidelines Trichloroacetic Acid 0.100mg/L, Dichloroacetic Acid 0.100mg/L
“Chloroacetic acids are produced in drinking water as by-products of the reaction between chlorine and naturally occurring humic and fulvic acids. Concentrations reported overseas range up to 0.16mg/L and are typically about half the chloroform concentration. The chloroacetic acids are used commercially as reagents or intermediates in the preparation of a wide variety of chemicals. Monochloroacetic acid can be used as a pre-emergent herbicide, dichloroacetic acid as an ingredient in some pharmaceutical products, and trichloroacetic acid as a herbicide, soil sterilant and antiseptic.” Australian Drinking Water Guidelines – National Health and Medical Research Council…
Dookie (Victoria) – Chloral Hydrate
Highest Detections only 2010/11
Dookie 22ug/L [mean 10ug/L] Chloral Hydrate 2010/11
2004 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.02mg/L
2011 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.1mg/L
“Chloral hydrate is a disinfection by-product, arising from chlorination of water containing naturally occurring organic material (NOM). Chloral hydrate has only been detected by Goulburn Valley Water since changing to a new contract testing laboratory in November 2007. The Department of Health is currently conducting a study into the detection of chloral hydrate across Victoria.”
Dookie (Victoria) Iron
2017/18: Dookie (Victoria) – Iron 0.3mg/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
2018/19 – Dookie (Victoria) – Blue Green Algae
During the reportable period three incidents were notified to DHHS, including Dookie, Kyabram and Tongala which were directly attributable to unprecedented characteristics of a major BGA bloom in the Central Goulburn Irrigation District. The bloom persisted for more than six months affecting sixteen plants directly in GVW’s Central District. BGA created numerous challenges at the water treatment plants resulting in operational changes on a regular basis to ensure customers continued to receive safe drinking water. Water was carted to one of our regulated towns (Goulburn Weir) during the period their raw water supply was impacted by the BGA as levels exceeded the recreational limit. Water carting continued for a month with routine notifications to the customers affected…