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Incidents Online Tool

The Risk Edge Group is proud to support our industry with Incidents Online, our historical curated database of online water quality and industry-relevant incidents.

  • Incidents Online helps organisations to identify patterns or trends in water quality incidents over time, allowing them to help predict and prevent future incidents.
  • Incidents Online also serves as a reference tool for researchers and policy-makers to study the causes and effects of water quality incidents, and to develop effective risk mitigation strategies.
  • By having access to Incidents Online, individuals and organisations can better prepare themselves to respond to future water quality incidents, by learning from past experiences and implementing appropriate measures to minimise impacts.
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wdt_ID Year Topic Location Contaminant / Issue Event Impact Reference
66 2016 Drinking water Not stated Various Verizon reported that 'Kemuri Water Company' had experienced data breaches of its SCADA system through hacking. The Operational Technology (OT) end of the water district relied on antiquated computer systems running operating systems from ten plus years ago. Further, only a single employee was capable of administering the system. The system ran the water district’s valve and flow control application that was responsible for manipulating hundreds of Programmable Logic Controllers (PLCs), housed customer Personally Identifiable Information (PII) and associated billing information, as well as KWC’s financials. Illegal cyber activities resulted in manipulating the PLCs that managed ducts and valves. No clear motive for the attack was found however the low level of damage incurred was more due to the fact that the hacktivists did not have specific knowledge of the SCADA system.
"Having internet facing servers, especially web servers, directly connected to SCADA management systems is far from a best practice. Many issues like outdated systems and missing patches contributed to the data breach—the lack of isolation of critical assets, weak authentication mechanisms and unsafe practices of protecting passwords also enabled the threat actors to gain far more access than should have been possible. KWC’s alert functionality played a key role in detecting the changed amounts of chemicals and the flow rates. Implementation of a layered defense-in-depth strategy could have detected the attack earlier, limiting its success or preventing it altogether."
Information provided by Nahim Nehme, Griffith Council.
Issues were caused with unauthorised dosage of water treatment chemicals, the water flow rate, and disruptions with water distribution and access to over 2.5 million customer records Verizon
67 2016 Drinking water Flint, Michigan, USA Lead Flint, under a state-appointed emergency manager, switched to Flint River water in April 2014 from the Lake Huron supply that Detroit uses to save money. Complaints about the water began within a month of the move. But Flint did not return to Detroit water until October 2015 after tests showed elevated levels of lead. Corrosive water from the river, caused more lead to leach from Flint pipes than Detroit water did. As many as 9,000 children have been affected by adverse lead levels SBS Link
68 2015 Raw water Grafton, NSW, Australia Chlorine Repairs were being undertaken on pipework for a chlorination system located in a shed at the chlorination plant. Chlorine is fed by suction as water flows from a booster pump. The isolation valve sometimes does not open immediately, but the worker undertaking the repairs was not aware of this (other workers who were aware of the issue have been waiting until they hear and see the valve open). The isolation valve did not open and when the booster pump was turned back on, the pressure from the closed valve resulted in failure of the pipework. The chlorine injector point is only 300 mm from the section of pipe which failed, and there was insufficient dilution to prevent release of chlorine gas into the shed. Previous risk assessments had considered it impossible for there to be a chlorine gas leak at this location due to the dilution of chlorine with water. The isolation points for the chlorine are approximately 150 metres from the shed so it took several minutes to shut the chlorine off. Due to the chlorine not being previously considered as a risk, a rescue plan was not in place and Breathing Apparatus was only located at the isolation point.

Actions taken as a result of this incident include:
* Procedure for turning the pump on and off and isolating the valves were mounted on the control panel.
* Isolation valves on chlorine gas feed lines were installed outside the shed.
* A Chlorine sensor was installed within the shed with an external visual alarm.
* Workers were reminded at a Toolbox talk that machinery faults are to be advised immediately to supervisors, and the faulty machinery tagged out.

This was a Workcover notifiable incident.
Operator off work for 1 day (precautionary) Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
70 2014 Drinking water Lower Clarence area, NSW, Australia Dirty Water The area impacted by this incident is the area supplied with drinking water from the 21ML terminal reservoir at Maclean, NSW. This area included the towns of Maclean itself, Yamba, Iluka, Brooms Head, Gulmarrad, Ashby, Harwood, Palmers Island, Woombah, Angourie and Wooloweyah. The population of this area is estimated to be approximately 20,000 people. As Council's supply is unfiltered, until about 2004 river extraction occurred regardless of raw water quality and there was very low or no chlorine reticulation in the area serviced by the terminal reservoir, the reticulation serviced by the reservoir had significant biofilm growth. Following commissioning of a permanent supplementary chlorine dosing point at the reservoir in late 2013, in the week before Christmas 2013 the Public Health Unit requested Council to significantly increase the chlorine dose and strongly implied that they would require Council to issue a boil water alert if it didn't increase the dosing rate. Council raised concerns that the sudden increase in chlorine residual would result in rapid biofilm die-off and subsequent dirty water events, but the PHU contended this was preferable to a potential E. coli event. For the first three months of 2014 Council received abnormally high numbers of dirty water complaints due to biofilm die-off, with up to 20 customer reports of dirty water a day compared with a "normal" rate of 1 to 2 reports. Council's proposed approach to supplementary chlorination, which was circumvented by the PHU implying they would require a boil water alert if the dosing rate was not significantly increased, was to gradually increase the dosing rate so that biofilm die-off in the reticulation (and hence dirty water events) were minimised. It is considered the high incidence of dirty water reports significantly damaged customer's confidence in the quality of water supplied.
Moderator's Note: Readers are reminded of the first principle of the Australian Drinking Water Guidelines: "The greatest risks to consumers of drinking water are pathogenic microorganisms. Protection of water sources and treatment are of paramount importance and must never be compromised."
20,000 customers having frequent dirty water events for 3 months Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
71 2013 Drinking water Minnie Waters, NSW, Australia E. coli found leading to a Boil Water Alert Minnie Waters is a coastal village of around 250 people located approximately 50km east of Grafton. Following E. coli detections during routine sampling, Minnie Water residents were advised to boil water from 8th February 2013 until 12th February 2013, and then again from the 6th March 2013 until the 13th March 2013. In response to both E. coli detections Council added liquid chlorine to the reservoir, flushed the system, and inspected the reservoir. The first detection was thought to be related to extraction from Lake Minnie Water (the raw water supply) during a high rainfall event, introducing a high organic load to the system. Since that event, the Minnie Water scheme has selective extraction, where operators cease extraction during extreme wet weather events. For the second event, there was no obvious contamination source. The top section of the reservoir is mesh and it is thought that during a significant East Coast Low event with both heavy rainfall and gale force winds, contaminated stormwater runoff from the roof was blown back into the reservoir through the mesh. 250 customers on boil water alert for 4 days Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
72 2013 Drinking water Ashby, NSW, Australia E. coli found leading to a Boil Water Alert During a flood event in January 2013 a mains break on a dead end line occurred in an area under floodwater. The break was subsequently determined to be due to a thrust block moving. The dead end line was isolated by closing a stop valve until repairs to the main could be made when access was available after the flood. Due to the possible ingress of flood water to the main, a precautionary boil water advice was issued to residents serviced by the line when the stop valve was opened. Despite flushing of the line and chlorine dosing at the repair site, E. coli was detected for three tests following repair of the line which indicates that flood water had entered the main. 20 customers on a boil water alert for 4 days Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
73 2013 Drinking water Lower Clarence area, NSW, Australia E. coli found leading to a Boil Water Alert The area impacted by this incident is the area supplied with drinking water from the 21ML terminal reservoir at Maclean, NSW. This area included the towns of Maclean itself, Yamba, Iluka, Brooms Head, Gulmarrad, Ashby, Harwood, Palmers Island, Woombah, Angourie and Wooloweyah. The population of this area is estimated to be approximately 20,000 people. Due to the distance from the chloramination point these towns historically had very low chlorine residuals. Following E. coli detection at more than one location during routine sampling, residents in these areas were advised to boil water from 16th May 2013 until 21st May 2013. Council's immediate response included adding chlorine to various reservoirs, flushing the network, and visual inspections of reservoirs. Council also established a temporary chlorine dosing point at 21ML reservoir. Numerous reservoirs were emptied and cleaned out, although no obvious contamination source was located. It is thought that the E. coli detections may have been related to the use of an old bypass lines at the reservoir site, which was not flushed prior to use, and may have had aged water within. There is now a permanent supplementary chlorine dosing point at the terminal reservoir. 20,000 customers on a boil water alert for 5 days Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
75 2013 Raw water Shannondale, NSW, Australia Operational issue Selective offtake at different depths in a dam is achieved with the use of removable baulks. The baulks are raised and lowered into position using a crane, and there is a mechanism which unlatches the crane hook from the baulk when it encounters sufficient force (i.e. when it is stopped by the baulk underneath). The baulks are lowered through a slot in the dam offtake tower. The operator was changing baulks when the baulk being lowered missed the slot and hit the deck of the offtake tower with sufficient force to unlatch the hook. The baulk then fell sideways. Baulk changing procedures were modified
* A safety chain is placed around the latching mechanism preventing it opening until the baulks are located in the slot, when the chain is removed, and
* Baulk changes are undertaken when there is no wind.
Nil (near hit) Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
76 2012 Drinking water Maclean, NSW, Australia E. coli found leading to a Boil Water Alert Maclean is a town of around 2600 people located on the Clarence River, approximately 25km upstream of Yamba. Due to the distance from the chloramination point the town historically had very low chlorine residuals. Following an E. coli detection during routine sampling, around 200 residents in a very defined area of the top part of Maclean fed by the “Lookout Reservoir” were advised to boil water from 21st December 2012 until 7th January 2013. In response to e.coli detection Council added liquid chlorine to the reservoir, flushed the system, inspected and cleaned the reservoir. After these actions there were still no obvious signs of the contamination source. During the event despite the reservoir chlorine dosing there was only a very small residual detected in the reticulation, although there was good residual in the reservoir. This was initially thought to be due to a contaminant in the reticulation creating chlorine demand; however, it was subsequently determined that as the reservoir was filled by pumping through the reticulation the low residual in the reticulation was due to the low residual at the pumping station. The reservoir was also bottom fed. Since this event permanent supplementary chlorine dosing was installed in Maclean (before the pump station) and the reservoir also changed to a top fill. The timing of this E. coli detection just before a holiday period made management of the incident difficult as many suppliers were closed; this incident also demonstrated the important of having adequate supplies on hand in case an incident occurs over a holiday period. Moderator Note: Timeline was end 2012 into beginning 2013. 200 customers on a boil water alert for 18 days. Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
77 2012 Drinking water Glenreagh, NSW, Australia E. coli found leading to a Boil Water Alert Glenreagh is a village of around 400 people located on the Orara River approximately 45km south of Grafton. Following an E. coli detection during routine sampling, Glenreagh residents were advised to boil water from 7th December 2012 until 12th December 2012. In response to E. coli detection Council added liquid chlorine added to the reservoir, flushed the system, and inspected the reservoirs. The chlorinator was also investigated and it was found to have failed due to a problem with the inlet valve. Since this event, the inlet valve at Glenreagh now has regular maintenance and on-line telemetry monitoring of the chlorinator has been introduced. 400 customers on boil water alert for 5 days Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
78 2011 Drinking water Copmanhurst, NSW, Australia E. coli found leading to a Boil Water Alert Copmanhurst is a village of around 250 people located on the Clarence River approximately 40km upstream of Grafton. Due to the distance from the chloramination point the village historically had very low chlorine residuals. Following an E. coli detection during routine sampling, Copmanhurst residents were advised to boil water from 5th May 2011 until 19th May 2011. In response to e.coli detection Council added liquid chlorine to the reservoir, flushed the system, inspected and cleaned the reservoir. Upon cleaning the reservoir a snake was located and was the suspected cause of contamination. While snakes are cold blooded, it is thought that E. coli may have been introduced from a warm blooded animal which the snake had eaten. Since this event, the reservoir at Copmanhurst is now offline, with the village pressure coming from an alternate larger reservoir approximately 20km from Copmanhurst. Additionally, there is now a supplementary chlorine dosing point on the line out to Copmanhurst. 250 customers on boil water alert for 14 days Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
79 2011 Drinking water Grafton, NSW, Australia Chlorine An operator transporting 90kg chlorine gas cylinders in the rear of a utility (less than the quantity for which a Dangerous Goods motor licence is required) swerved to avoid a kangaroo and rolled the vehicle several times. As the vehicle was carrying chlorine cylinders this was classified by attending emergency services as a Hazmat incident. Toolbox talks were given to staff regarding not swerving to avoid wildlife. Operator was off work for 3 months recovering from injuries sustained in motor vehicle accident; motor vehicle written off; Supplier advised chlorine cylinders sustained no damage Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
81 2011 Sewage Maclean, NSW, Australia Sewage Staff attended a pump blockage of the duty pump at a sewage pump station just before normal finishing time and determined that the blockage could be cleared the following day as a crane was required to lift the pump. They turned the duty pump to "off" on the assumption that the electronic controller would then automatically use the standby pump. However the controller program did not automatically start the standby pump. While a high level alarm was generated, a thunderstorm the previous evening had damaged the main telemetry dialler, although this was not known at the time. The backup telemetry dialler was being relocated to a new building at the STP the following morning and had been disconnected from the telephone that day. The manufacturer of the pump controller was advised of the incident so they could modify their standard program. Up to 200kL raw sewage environmental overflow Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
83 2011 Sewage Maclean NSW, Australia Sewage The end weir penstock decant in an STP treatment tank consists of two aluminium gates with a centrally mounted actuator which drives through a distribution gearbox to four bevel gearboxes. These gearboxes drive bronze nuts that move threaded stems located at each end of the gates up and down. The gearbox mechanism on one of the threaded stems failed with the gate in the lowered position. When the weir began to raise, the overtorque mechanism did not operate and only one side of the gate was raised, which significantly distorted the gate. Subsequent investigation determined:
* The supplier training incorrectly advised that the gearbox did not need to be greased, which was considered a primary cause of premature gearbox failure.
* The manual indicated the drive mechanism should be checked for wear but did not indicate what was unacceptable wear.
* The over-torque relay did not operate because the trip circuit terminals had been bridged (apparently when installed) and this bridge had not been removed.
One treatment tank out of service for 8 weeks while repairs to decant mechanism undertaken Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
85 2010 Drinking water Saratoga Springs, Utah, USA Campylobacter The City of Saratoga Springs, Utah, issued a boil water order for the northern half of the city this week (15 May 2010) after Campylobacter bacteria were discovered in the city's culinary water system. Posted 17/05/10 Information shared by Nahim Nehme, Griffith City Council, NSW, Australia Thirteen subdivisions affected and told to boil water or drink bottled water Food Safety News Link
86 2010 Drinking water Longreach, QLD, Australia E. coli Regular monitoring of the Longreach Water Supply has detected minute traces of E. coli in the Longreach’s Water Supply (January 2010). As a precaution, Council is advising town residents to use cooled, boiled water for drinking, cooking, washing raw foods, making ice and cleaning teeth. Apparently a 'mechanical fault' at the treatment plant was thought to be responsible for the detection of E. coli although the nature of the fault was not elaborated. Posted 17/05/10 Information shared by Nahim Nehme, Griffith City Council, NSW, Australia Residents had to boil water Long Reach Website Link
87 2010 Drinking water Nerang, Gold Coast, QLD, Australia E. coli E. coli was detected during routine testing. Residents were required to boil their water. No cause of the event was known at the time of posting. 2500 homes affected with a boil water alert Courier Mail Link
88 2010 Drinking water Bowen, QLD, Australia E. coli Whitsunday Regional Council issued a boil water notice after recent tests on the Bowen water system found Escherichia coli in the treated water. Recent rainfall was thought to have contributed to the presence of the bacteria in the water supply. (Posted 26/03/10 Information shared by Nahim Nehme, Griffith City Council, NSW) Bowen residents were required to boil their water for more than a week Dail Mercury Link
89 2010 General operations Maclean, NSW, Australia Operational issue An operator was loading a roll of 100mm poly pipe onto the tray of a truck using a hiab crane. Due to the diameter of the roll the pipe had to be stood up in the truck as it was too wide to lay flat. Before the roll could be secured, it shifted and knocked the operator off the truck. The operator fell to the ground, landing on his head, and the roll of pipe landed on him. Following this incident:
* Procedures were modified to remind staff that consideration needs to be given to release of stored energy in situations where the load may be coiled, strapped, fastened, etc, and in particular consideration of whether additional strapping is required and how best to release strapping
* Pipe is delivered direct to the job site where possible,
* Where staff are transporting pipe, a caged trailer is used rather than standing the pipe roll up in the back of the truck.

This was a Workcover reportable incident.
Operator was hospitalised for several weeks and did not return to full duties for 2 years. Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
92 2010 Drinking water Wooli, NSW, Australia Chlorine A village operator (who was not trained in chlorine plant operation) attended a chlorination plant following a power outage to check the system was working and heard the chlorine alarm sounding. He decided to open the door and was met with chlorine. He shut the door and called appropriately qualified staff to address the chlorine leak. As a result of this incident:
* Extraction fans and strobe warning lights were installed on all chlorination sheds
* Signs have been placed on all chlorination sheds "Do not enter whilst light is flashing"
* Gas sensors have been connected to force the extractor fans and strobe light and also generate a telemetry alarms
* Procedures updated and toolbox talks given regarding chlorine safety and that only appropriately trained staff are to open the door if the chlorine alarm is sounding.

This was a Workcover reportable incident.
Operator off work for 1 day; however the investigating Workcover inspector advised they considered this incident as a "near fatality". Greg Mashiah, Manager Water Cycle, Clarence Valley Council pers. communication. February 2016.
93 2009 Drinking water Jindabyne, NSW, Australia Sewage A mega litre of raw sewage flowed into Lake Jindabyne, the source of the town's water supply. Snowy River Shire Council confirmed a leak at a sewer pump station located behind the Jindabyne Bowling Club and estimated between 0.5 and 0.8 mega litres of sewage spilled into the lake over a three-day period.
(Posted 01/09/09)
Tourists and residents had to boil water or drink bottled water for around two weeks Area Health Service Link
94 2009 Drinking water Smiggins Holes, NSW, Australia Unknown A malfunction of the water supply system (operated by the National Parks and Wildlife Service) caused the tank to run out of water. Some sort of bacteria or virus, picked up from the bottom of the tank, was thought to have been flushed down the lines and to taps. Results of testing on earlier water samples proved inconclusive but given the number of people who fell sick and the timing of the gastric outbreak it was thought that the incident is most likely linked to contamination of the water supply. Close to 120 guests were struck down with gastric illness Summit Sun Link
95 2009 Drinking water Brisbane, Queensland, Australia Fluoride overdose Up to three safeguard systems failed at the North Pine water-treatment plant allowing drinking water to be released to residents with fluoride levels that were originally thought to be 20 times the legal limit (30 milligrams of fluoride per litre, rather than the 1.5mg/litre maximum) for a duration of three hours on May 2. A follow-up investigation found that levels were actually 19.4 mg/L and only a small number of people had been affected compared to those previously thought to have been exposed. Originally thought to have affected 4,000 properties affected but refined to 211 children at a YMCA camp and four houses Healthstream Link
96 2009 Drinking water Lithgow, NSW, Australia Concern over heavy metals, particularly nickel General Practitioners stated that Lithgow has high levels of chronic illnesses such as diabetes and heart disease and these doctors wanted to know if there were any links to water which is pumped into the city's water supply from the Clarence Colliery. Water quality testing results (mandatorily carried out for the NSW Drinking Water Quality Monitoring Program) showed that Lithgow's water supply routinely meets the Australian Drinking Water Guidelines for a range of parameters including nickel. None - perception-based issue proven to be unfounded based on water quality testing results ABC Link
97 2008 Drinking water Alamosa, Colorado, US Salmonella, Giardia & Cryptosporidium were all found in the town's water supply The town, of about 8,500 residents, gets its water from a deep well system. Water sourced from the aquifer is not chlorinated. A disease outbreak of salmonellosis occurred in the town. The contamination of the water supply was still unknown at the time of writing. 400 cases of illness and up to 16 people being hospitalised CBS Link
98 2008 Drinking water Zimbabwe (affecting 42 of 62 districts including the capital, Harare) Vibrio cholerae Contamination of the Limpopo River with contaminated river water also passing the border into South Africa and causing cholera cases in South Africa's Limpopo province. Unclear of the cause of the outbreak but the Limpopo River supplies many dams used for drinking water supply and the town of Beitbridge is supplied by the river directly.
(See also the following for water resource information
565 deaths and 12,546 illness at the time of posting (22/01/09) Relief Web Link
99 2008 Drinking water Northampton Town, Daventry, South Northamptonshire and areas in Wellingborough, East Midlands, UK Cryptosporidium An estimated 250,000 individuals were put at risk by the exceedance in cryptosporidial oocysts found in the water supply leaving Pitsford Reservoir during the period 19 to 24 June 2008. The source of the contamination was identified as a small rabbit that had gained access to the treatment process. Further testing of the water samples taken from the distribution system, and also from the rabbit, carried out by the Cryptosporidium Reference Laboratory in Swansea, confirmed that they were of the same strain, identified as a rabbit genotype. This case is significant as it appears to be the first where a Cryptosporidium species from a rabbit has been found to infect humans. 250,000 individuals were put at risk, 29 cases of cryptosporidiosis at the time of posting UK National Archives Link
100 2007 Drinking water Lilla Edet, Sweden Norovirus A large outbreak of norovirus gastroenteritis was caused by contaminated municipal drinking water, in Lilla Edet, Sweden. Costs associated with the outbreak were collected via a questionnaire survey given to organizations and municipalities involved in or affected by the outbreak. Total costs including sick leave, were estimated to be ∼8 700 000 Swedish kronor (∼€0·87 million) (Larsson et al 2014). About 2400 (18·5%) of the 13 000 inhabitants in Lilla Edet became ill. LARSSON, C., ANDERSSON, Y., ALLESTAM, G., LINDQVIST, A., NENONEN, N. and O. BERGSTEDT (2014) Epidemiology and estimated costs of a large waterborne outbreak of norovirus infection in Sweden. Epidemiology and Infection Volume 142(3): 592-600
101 2007 Drinking water Galway, Ireland Cryptosporidium Historically high precipitation levels and the lake reaching the highest level on record were linked to exceedances above the guideline level of less than 1 oocyst/10 litres in the finished water. 182 cases notified Pelly H, Cormican M, O'Donovan D, Chalmers R, Hanahoe B, Cloughley R, et al. A large outbreak of cryptosporidiosis in western Ireland linked to public water supply: a preliminary report. Euro Surveill 2007;12(5):E070503.3.
102 2007 Drinking water Røros, Norway Campylobacter The municipal waterworks, which supplies Røros town, provides 3600 people with tap water. Groundwater comes into the system from two wells drilled into an aquifer under an island in a lake northeast of Røros. The water is not chlorinated or disinfected before reaching consumers. While tap water was identified as the most probably source of the infection, Campylobacter was not found in the town's water. However, several events that might have caused pressure fall and influx of contaminated water into the water distribution system were noted. On two occasions, pressure fall was noticed and because parts of the distribution system were outdated, it is likely that the pressure fall caused ingress of contamination leading to the outbreak. 105 cases confirmed Irena Jakopanec, Katrine Borgen, Line Vold, Helge Lund, Tore Forseth, Raisa Hannula and Karin Nygård (2008) A large waterborne outbreak of campylobacteriosis in Norway: The need to focus on distribution system safety. BMC Infectious Diseases 2008, 8:128.
103 2007 Rainwater Esperance, WA, Australia Lead The Esperance Port Authority exported lead carbonate. This material was mined at the Magellan mine near Wiluna some 900 km north of Esperance by Magellan Metals Pty Ltd and railed to Esperance. The Esperance Port Authority handled this material in bulk, and there were lead emissions from the Port and contamination of the town site and adjacent environs. The extent of those emissions and any contamination of the town site are matters that are currently the subject of prosecution by the DEC. (Posted 01/09/09) Many rainwater tanks had levels of lead and nickel exceeding the maximum levels specified in the 2004 Australian Drinking Water Guidelines. Blood lead levels in the population were also found to be elevated. WA Public Health Link
104 2006 Sewage Yamba, NSW, Australia Biosolids Utility staff were using a 240V portable pump to empty a sewage sludge lagoon into a Geotube when they were called away to attend a reticulation blockage. The blockage was not cleared until after dark, and the staff inadvertently left the pump turned on when they left the STP. This eventually resulted in failure of the Geotube and considerable biosolids spillage around the STP. As a result of this incident a timer was purchased to use on the power outlet. Moderator Note: Timeline approximate. Cleanup of spilled biosolids required Mashiah, G. (2009) Here we go again? Sharing experiences of Incidents in the NSW Water Industry. NSW AWA Regional Conference, Port Macquarie
105 2006 Sewage Yamba, NSW, Australia Sewage A raw sewage overflow occurred from a pump station without an alarm being generated. The pump station has a low level float switch to operate the duty pump and a high level float switch which operates the standby pump and also generates a telemetry alarm. The high level float switch was wired as "normally open" and it was determined that there was a break in the cable; thus the pump control remained "open circuit" and could not start the standby pump or generate an alarm. Subsequent investigation of the utility's sewerage network indicated about 20% of sensors were wired as "open circuit". These have been changed to closed circuit so if the cable breaks it will also send an alarm - this is "safe fail" in that if the cable fails it will send an alarm, and the specification for future work requires sensors to be wired as closed circuit. Moderator Note: Timeline approximate. Raw sewage environmental overflow Mashiah, G. (2009) Here we go again? Sharing experiences of Incidents in the NSW Water Industry. NSW AWA Regional Conference, Port Macquarie
106 2006 Bottled water Port Kent, NY, US Diatoms and total coliform bacteria North Country Spring Water, Ltd bottled water was found to be contaminated. May have been caused by a potential surface water contamination event at the water source and/or a temporary breakdown in the company's filtration system None confirmed FDA Link
111 2005 Rainwater Aged care facility, Queensland, Australia Multiple serotypes of Salmonella, including Muenchen, Chester, and Subspecies 3b Salmonellosis outbreak at an aged care facility thought to be caused by a contaminated rainwater tank. Salmonella Subspecies 3b was isolated from water from the facility’s rainwater tank. The tank water was also heavily contaminated with E. coli. The source was thought to be amphibians or reptiles. 8 OzFoodNet (2005) © Enhancing foodborne disease surveillance across Australia: Quarterly report, January to March 2005: Communicable Diseases Intelligence 29:197-8
112 2005 Sewage Yamba, NSW, Australia Operational issues The flocculant storage volume at the then only STP with artificial flocculation was such that, for a full truckload delivery there was only about 7 days supply remaining. The utility had a period supply contract which permitted use of other suppliers if the preferred supplier was unable to provide service. On one occasion the supplier did not arrive on the nominated day. When contacted, they apologised and indicated that they would deliver in four days, when the utility would have about three days flocculant supply remaining. Again, they failed to arrive and when contacted they advised that they would be at least another seven days. While the utility immediately arranged for an alternative supplier, delivery took several days with the result that the utility was unable to dose flocculant at the desired level.

While the utility has now commissioned other STPs using the same flocculant, and if a similar situation occurred it would be possible to transfer flocculant from another STPs, during floods the various STPs are isolated for up to a week. As part of the procedures when the BOM issues a flood watch, the volume of all chemicals required at STPs is checked and supply ordered if necessary. Fortunately a flood watch generally gives four or five days notice.
Moderator Note: Timeline approximate.
Lower level of sewage treatment for four days with impact on effluent suspended solids and phosphorus Mashiah, G. (2009) Here we go again? Sharing experiences of Incidents in the NSW Water Industry. NSW AWA Regional Conference, Port Macquarie
113 2004 Sewage Yamba, NSW, Australia Operational issues The decant trough on the then single activated sludge tank at the Yamba Sewage Treatment Plant (STP), which was installed in 1999, has a centrally mounted motor on a bridge over the tank and the trough is raised and lowered with two steel ropes connected at either end of the trough. The maintenance manual for the STP did not indicate that any maintenance or checking of the steel ropes was required and, as this was the first mechanism of this type used by the utility, it was unaware that the steel ropes should be changed after a period of service. Given the STP is located about 500 metres from the ocean, the steel ropes are subject to attack from both chlorides and sulphides. On the Thursday before Easter one steel rope snapped, dropping one end of the trough into the activated sludge tank. Limit switches controlling the raising and lowering of the trough had been installed only on the end which had dropped into the tank. When the decant cycle started, the side which still had a rope was raised until it hit the bridge. The motor had been installed with mounting bolt holes larger than the Australian Standard, and it appears the strain caused the motor to move as it pulled a coupling with an overload sensor apart and thus the motor did not stop until it burned out. When staff attended the STP the steel rope was under significant tension, so access to the bridge was prohibited due to the risk of failure until a fitter could attend and release the strain. The largest daily inflow to the plant generally occurs over Easter; thus the utility had a very limited opportunity to put in temporary decant measures. As a result of this incident:
* a limit switch was installed on the other side of the bridge,
* a new maintenance schedule was introduced which changed the steel ropes annually,
* all subsequent STPs have been constructed with two treatment tanks so sewage treatment can still occur if there is equipment failure in one tank.

Following the incident, discussion with other utilities with similar decant mechanisms indicated that they had experienced identical failures, but had not shared this information with other utilities. Despite advising the designer of the issue and recommending that they advise other customers with similar mechanisms that the maintenance manual needed to be updated to include changing wire ropes, it is understood that no such information was circulated.
* Bypass of STP (screening of raw sewage only) for approximately 12 hours
* Manually operated pumping used for decanting during Easter period (permanent repairs unable to commence until Tuesday due to Easter break)
Mashiah, G. (2009) Here we go again? Sharing experiences of Incidents in the NSW Water Industry. NSW AWA Regional Conference, Port Macquarie
115 2003 Drinking water Yamba, NSW, Australia Sewage A developer construction contractor tapped subdivision fire hydrants onto a PVC sewer rising main, which was only detected when the hydrants were tested and there was no flow, followed by what was obviously pumped flow (the water reticulation is supplied by gravity). It is understood that the contractor was using inexperienced staff with inadequate supervision. Nil Mashiah, G. (2009) Here we go again? Sharing experiences of Incidents in the NSW Water Industry. NSW AWA Regional Conference, Port Macquarie
117 2002 Drinking water Maricopa County, Arizona, USA Naegleria fowleri In 2002, two five-year olds living in Maricopa County, Arizona became infected with Naegleria fowleri and subsequently died of Primary Amoebic Meningitis (PAM), 72 hours after hospital admission. The water supply provided to the children’s homes was sourced from an untreated groundwater supply and provided by a private water company. N. fowleri was subsequently isolated from the groundwater supplied to one of the children’s homes and from the refrigerator filter from the second child’s grandparents’ home (at which the child spent a lot of time). The pathogen was also found in bathroom and kitchen pipes as well as filtered bathwater from both homes. 2 deaths Reynolds, K.A. (2006) Newly Identified Tap Water Sources of Pathogenic Amoeba. Water Conditioning & Purification. January 2006. 58-60.
118 2001 Drinking water Dracy Le Fort, Burgundy, France Cryptosporidium hominis (found in 19 of the patients) Not stated but tap water was found to be the only common risk factor. 563 cases Dalle F, Roz P, Dautin G, Di Palma M, Kohli E, Sire-Bidault C, et al. Molecular characterization of isolates of waterborne Cryptosporidium spp. collected during an outbreak of gastroenteritis in South Burgundy, France. J Clin Microbiol 2003; 41:2690-3.
119 2000 Drinking water Clitheroe, Lancs, UK Cryptosporidium Local investigations showed that a spring which feeds a local reservoir is in an animal grazing area. The Cryptosporidium was typed as originating from an animal source. 45 cases UK National Archives Link
120 2000 Drinking water Walkerton, Ontario, Canada Primarily E. coli O157:H7 & Campylobacter jejuni Poor chlorination plant performance, storm in catchment, poor operating practices. 7 deaths (including a 2 year old child) and 2,300 illnesses O’Connor, D.R. (2002) Report of the Walkerton Inquiry: The Events of May 2000 and Related Issues. Part One: A Summary. Ontario Ministry of the Attorney General. ISBN: 0-7794-2558-8
121 2000 Drinking water England and Wales Cryptosporidium Heavy rainfall and flood alerts preceded cases of cryptosporidiosis. Oocysts were thought to infiltrate the reservoir from springs. The oocyst persisted in the distribution system after the water supplier had chosen a different water source. Persistence of oocysts may have been due to entrapment of the oocysts in the biofilm. 58 cases Howe AD, Forster S, Morton S, Marshall R, Osborn KS, Wright P, Hunter PR. Cryptosporidium oocysts in a water supply associated with a cryptosporidiosis outbreak. Emerg Infect Dis 2002;8(6):619-24.
122 2000 Drinking water Northern Ireland Cryptosporidium Seepage into the distribution system from human sewage from a septic tank and wastewater from a blocked drain were found to be responsible for waterborne cryptosporidiosis cases between 2000 and 2001. 347 laboratory confirmed cases Glaberman S, Moore JE, Lowery CJ, Chalmers RM, Sulaiman I, Elwin K, et al. Three drinking-water-associated cryptosporidiosis outbreaks, Northern Ireland. Emerg Infect Dis 2002;8(6):631-3.
123 1999 Drinking water Washington County Fair, NY State, US E. coli O157:H7 (positive confirmation in the septic tank) & Campylobacter jejuni Attendants at a county fair drank beverages made with water accessed from the groundwater system (Well 6). A septic system associated with a dormitory on the fairground site was suspected of contaminating the well – particularly given that E. coli O157:H7 was also found in the septic system and hydraulic connectivity was established between the well and the septic system. 2 deaths and 71 people hospitalised of which 14 people developed haemolytic uraemic syndrome CDC (1999) Outbreak of Escherichia coli O157:H7 and Campylobacter among attendees of the Washington County Fair – New York 1999. Morbidity and Mortality Weekly Report 48(36), 803-804.
124 1998 Drinking water Sydney, NSW, Australia Cryptosporidium & Giardia Storm in catchment and supposed breakthrough of filtration plant. Hazards found in the water supply but no disease incidence noted in the community Anon (1998) Protozoa in Sydney. Healthstream. Issue 11. September 1998
Byleveld, P.M., Hunt, A. and Jeremy M McAnulty, J.M. (1999) Cryptosporidiosis in the immunocompromised: weighing up the risk. Medical Journal of Australia. 171: 426-428
125 1998 Drinking water Oulu, Finland Campylobacter jejuni Mains repair work causing a cross contamination of the unchlorinated groundwater supply with sewage. Approx. 3000 cases (one fifth of the town) Kuusi M., Nuorti J.P., Hanninen M.L., Koskela M., Jusilla V., Kela E., Miettinen I. and Ruutu P. (2005) A large outbreak of campylobacteriosis associated with a municipal water supply in Finland. Epidemiol Infect 133:593-601.
126 1995 Drinking water Northern Italy Cryptosporidium Oocysts were identified in sediment of a drinking water tank belonging to a drug rehabilitation community. Not specifically stated although the attack rate was 13.6% in HIV-negative individuals and 30.7% in HIV-positive individuals - the latter varying with CD4 cell count. Pozio E, Rezza G, Boschini A, Pezzotti P, Tamburrini A, Rossi P, et al. Clinical cryptosporidiosis and human immunodeficiency virus (HIV)-induced immunosuppression: findings from a longitudinal study of HIV-positive and HIV-negative former injection drug users. J Infect Dis 1997;176(4):969-75.
127 1993 Drinking water Milwaukee, WI, USA Cryptosporidium Poor water filtration plant performance and storm in catchment washing in human sewage. Estimated 100 deaths and 403,000 illness Mac Kenzie W.R., Hoxie N.J., Proctor M.E., Gradus M.S., Blair K.A., Peterson D.E., Kazmierczak J.J., Addiss D.G., Fox K.R., Rose J.B., et al. (1994) A massive outbreak in Milwaukee of cryptosporidium infection transmitted through the public water supply. N Engl J Med. 331(3):161-7
128 1993 Drinking water Northwest England Cryptosporidium Heavy rainfall preceded a cryptosporidiosis outbreak. One water source was found to drain surface water directly from a field housing livestock, the natural sandstone barrier being bypassed. A case-control study showed significant correlation with drinking unboiled tap water. 47 cases Bridgman SA, Robertson RMP, Syed Q, Speed N, Andrews N, and Hunter PR. Outbreak of cryptosporidiosis associated with a disinfected groundwater supply. Epidemiol Infect 1995;115(3):555-66.
129 1990 Drinking water Burdine Township, Missouri, US E. coli O157:H7 Shortly before the peak of the outbreak, 45 water meters were replaced, and two water mains ruptured. The water supply was unchlorinated. 4 deaths and 243 illnesses Swerdlow DL, Woodruff BA, Brady RC, Griffin PM, Tippen S, Donnell HD Jr, Geldreich E, Payne BJ, Meyer A Jr, Wells JG, et al. (1992) A waterborne outbreak in Missouri of Escherichia coli O157:H7 associated with bloody diarrhea and death. Ann Intern Med. 1992 Nov 15;117(10):812-9
130 1988 Drinking water Camelford, UK Aluminium sulphate An inexperienced delivery contractor dumped 20 tonnes of concentrated aluminium sulphate solution into the wrong tank at the unmanned Lowermoor water treatment plant. Many people initially complained of taste issues in the water but no conclusive reports of illness were found Anon (2005) Report On UK Aluminium Incident Health Stream Issue 37 March 2005.
131 2018 Sewage Sydney, NSW, Australia Sewage overflow Approximately 2.8 million litres of untreated sewage overflowed into Toongabbie Creek near the junction with Parramatta River as a result of the pumps at Sydney Water’s Northmead Pumping Station being damaged and disabled following the collapse of the inner wall of the station on the morning of 21 October 2018.
The untreated sewage continued flowing several hundred metres downstream along Parramatta River, which is a key Sydney waterway.
Sydney Water was prosecuted, convicted and ordered to pay $175,500 plus the EPA’s investigation and legal costs. The Land and Environment Court found that the events leading to the discharge were foreseeable, environmental harm occurred, and that Sydney Water had control over the failure of the pumping station.
According to the EPA, the volume of the raw sewage was significant and there was an impact, in the form of actual, potential and likely harm, on the environment, including changes to the chemical and biological condition of Toongabbie Creek and the Parramatta River. NSW Environment Protection Authority (EPA)
132 2020 Sewage Sydney, NSW, Australia Sewage overflow A partial collapse of a Sydney Water sewage pipe and maintenance hole caused a blockage in the sewage system. This caused sewage to back-up and overflow at Dawson Reserve and two other locations near Flat Rock Creek, resulting in an overflow of approximately 16 million litres of raw sewage.
Sydney Water was prosecuted, convicted and fined $365,625. It separately committed $500,000 under an enforceable undertaking it entered into with the EPA which will be used to fund various environmental projects, including works within the Flat Rock Creek catchment.
Local residents were significantly impacted by the incident with reports of sewage odours and 39 people were temporarily relocated from their homes. NSW Environment Protection Authority (EPA)
133 2021 Sewage Sydney, NSW, Australia Sewage overflow A break in a Sydney Water rising main pipe, caused by erosion on the inside of the pipe, led to an incident that resulted in more than 3 million litres of untreated sewage overflowing into Arnotts Reserve and Powells Creek in Homebush and the Parramatta River.
Sydney Water entered into an enforceable undertaking with the EPA and agreed to pay $347,100 for environmental and community works plus the EPA’s legal and investigation costs.
The discharge was followed by a significant fish kill in Powells Creek, and Arnotts Reserve was closed to the public during clean-up for several weeks after the incident. NSW Environment Protection Authority (EPA)
134 2022 Raw water Hunter Region, NSW, Australia Discharge of contaminated water Cessnock City Council was fined $15,000 for breaching its EPA licence by allegedly failing to maintain a dam which allowed contaminated water to be discharged into the environment from the Cessnock Waste and Reuse Centre.
The EPA found that the equipment used to measure dam levels appeared to be installed incorrectly, giving a false indication that dam levels were lower. It also found that Cessnock City Council had allegedly failed to physically check the water levels leading to contaminated water discharging through the dam spillway.
Nil (near hit).
Risk of creating large-scale pollution events which can be destructive on both the environment and community.
NSW Environment Protection Authority (EPA)
135 2022 General operations Hunter Region, NSW, Australia Saline water discharge Bayswater Power Station, operated by AGL Macquarie Pty Ltd (AGLM), experienced a pump failure which resulted in saline water with elevated concentrations being discharged from the saline seepage collection system into Bayswater Creek. AGLM was fined $15,000 and given formal warnings by the EPA for failing to immediately report the incident as well as the failure to operate plant equipment in an efficient manner. The EPA also signalled to AGLM that it intends to vary Bayswater’s Environment Protection Licence to require that it review the adequacy of the seepage collection system and investigate the source of the elevated salinity in the seepage water. Nil (near hit). NSW Environment Protection Authority (EPA)
136 2023 Drinking water Kyneton and Malmsbury, Victoria, Australia Operational issue Coliban Region Water Corporation issued a Boil Water Advisory on the 11th and 12th of April 2023 for two regional towns in the State of Victoria following a burst water main and supply interruptions which had the potential for ingress into the system and to compromise the safety of drinking water. Nil (near hit) Coliban Water
139 2023 Drinking water Queenstown and Frankton, New Zealand Cryptosporidium A Boil Water Notice was issued by the Queenstown Lakes District Council (QLD Council) on 18 September 2023 following confirmation of multiple local cases of illness caused by the protozoa parasite, cryptosporidium.

A public health investigation into the cryptosporidiosis outbreak concluded that human faecal contamination of the source water in Lake Wakatipu was the most likely source of the infection.

Protozoa and other waterborne microorganisms can present a serious risk to public health, hence the importance of having a multi-barrier water treatment system. The Queenstown supply at the Two-Mile water treatment plant is currently operated without a protozoa barrier.

After receiving a compliance order from Taumata Arowai, the drinking water regulator, QLD Council put together a plan to install ultraviolet disinfection equipment at its water treatment plant. The temporary UV treatment equipment is estimated to be completed by 8 Dec 2023, and will be replaced by larger UV reactors once available.
Full impact yet to be determined.

The Boil Water Notice remains in force in some of the affected areas as of 11 Oct 2023.

As of 10 am, 6 Oct 2023, there are 62 confirmed cases of cryptosporidiosis and 18 probable cases. 24 cases are under investigation. 

The outbreak caused interruptions to local businesses, such as the temporary closure of a spa pool and swim class cancellations at other public pools.
Queenstown Lakes District Council
140 2023 Drinking water Glenreagh, NSW, Australia High turbidity levels Issues with the filtration plant at the Glenreagh Water Treatment Plant caused higher than normal turbidity levels to have been detected, which made drinking water in the Glenreagh water supply system unsafe from 11 October 2023. Clarence Valley Council and NSW Health issued a boil water alert as a result.
Initial attempts to resolve the high turbidity issue were unsuccessful, leading Council to pursue replacement filtration system options.
Full impact yet to be determined. Clarence Valley Council
141 2016 Drinking water Havelock North, New Zealand Campylobacter An outbreak of gastrointestinal illness campylobacteriosis occurred in Havelock North in August 2016, when the town’s drinking water became contaminated with campylobacter bacterium. Sheep faeces from paddocks near the water source was the likely source of the contamination.

Havelock North’s drinking water is sourced from an aquifer under the Heretaunga Plains. It was thought to be a confined aquifer and, as such, the town’s water supplier, Hastings District Council, did not treat the water drawn from the aquifer. Two bores on Brookvale Road on the town’s outskirts were used to access the water from the aquifer and to pump it into the reticulation system, through which it was delivered to consumers. After heavy rain inundated the nearby paddocks, contaminated water flowed into the aquifer where it was drawn through a bore and into the reticulation system by the bore pump.

Hastings District Council, Hawke’s Bay Regional Council and certain other parties with responsibility for Havelock North’s water supply were found to have breached the Drinking-water Standards and their legal duties in numerous respects, including, among others, failures to protect the water source, to take effective steps to assess contamination risks, and to adequately monitor compliance with permit conditions (such as keeping the bores in a safe and serviceable state).
Some 5,500 of the town’s 14,000 residents were estimated to have become ill with campylobacteriosis. Some 45 were subsequently hospitalised. It is possible that the outbreak contributed to three deaths, and an unknown number of residents continue to suffer health complications. Report of the Havelock North Drinking Water Inquiry – Department of Internal Affairs
143 2023 Drinking water Bristol Township, Bucks County, Philadelphia, USA Chemical spill On 25 March 2023, the Philadelphia Water Department (PWD) was notified by the Delaware Valley Early Warning System (EWS) that a synthetic latex product was spilled from the Trinseo facility into a tributary of the Delaware River in, Bucks County, 9 miles north of the Baxter Drinking Water Treatment Plant.
Staff from PWD and the Office of Emergency Management worked around the clock to respond to the event and averted potential risks to public health.
Extensive samples were collected, tested and analysed under two strategies respectively termed “intake monitoring” and “process monitoring”.
Nil Some lessons may be learned from the PWD’s response to the event. See details at:

Philadelphia Water Department

PWD’s testimony and presentation
144 2023 Drinking water Galway County, Ireland High manganese levels Due to elevated levels of manganese, Uisce Éireann (formerly Irish Water) and Galway County Council on 16 September 2022 issued a Do Not Consume Notice to all consumers on the Spiddal (An Spidéal) Public Water Supply. The Notice was lifted on 24 October 2022, however, a Boil Water Notice continued for a small portion of the network while additional remedial works were carried out. Approximately 5,676 customers were affected. Uisce Éireann
145 2023 Drinking water County Limerick, Ireland Cryptosporidium Following the detection of cryptosporidium at Shannon Estuary Water Treatment Plant, a Boil Water Notice was issued on 13 May 2023 by Uisce Éireann (formerly Irish Water) and Limerick City & County Council to residents in the areas serviced by the Foynes/Shannon Estuary Public Water Supply.

As of mid-October 2023, Uisce Éireann is working on plans to install an ultraviolet reactor at the Plant and the Boil Water Notice remains in place.
As of mid-October 2023, nearly 7,000 Limerick residents have been impacted by the Boil Water Notice. Irish Independent

Uisce Éireann
146 2023 Drinking water County Limerick, Ireland High turbidity levels Due to the possibility of inadequate disinfection caused by elevated turbidity, a Boil Water Notice was issued by Uisce Éireann (formerly Irish Water) and Limerick City & County Council on 31 May 2023 to consumers on the Doon Cooga Public Water Supply.
The high turbidity was caused by low water levels at the source.
Approximately 600 customers were affected. Uisce Éireann
147 2023 Drinking water County Mayo, Ireland Cryptosporidium Following the detection of cryptosporidium in the water supply, a Boil Water Notice was issued on 30 June 2023 by Uisce Éireann (formerly Irish Water) and Mayo County Council to customers serviced by the Clare Island Public Water Supply. The Notice remained in place for more than 3 months. Approximately 160 customers were affected. Uisce Éireann
148 2023 Drinking water County Limerick, Ireland Cryptosporidium Following the detection of cryptosporidium in the water supply, a Boil Water Notice was issued on 26 September 2023 by Uisce Éireann (formerly Irish Water) to customers serviced by the Cappamore Foillen Public Water Supply. Approximately 2,321 customers were affected. Uisce Éireann
149 2023 Drinking water Kildare County, Ireland High aluminium and manganese levels Due to elevated levels of aluminium and manganese, Uisce Éireann (formerly Irish Water) and Kildare County Council on 14 August 2023 issued a Do Not Consume Notice to all consumers in the Barrow Water Supply Zone. The Notice was lifted 4 days later. Approximately 1,177 customers were affected. Uisce Éireann
150 2023 Drinking water Inishbofin, County Galway, Ireland High manganese levels Due to elevated levels of manganese, Uisce Éireann (formerly Irish Water) and Galway County Council on 14 September 2023 issued a Do Not Consume Notice to all consumers on the Inishbofin Public Water Supply.

Notably, a similar Do Not Consume Notice also due to elevated manganese levels was issued to consumers on the Inishbofin Public Water Supply in September 2022 and lasted until December 2022. That incident was likely caused by extremely low water levels in Lough Fawna (lake) after a prolonged period of dry weather.
Approximately 156 customers were affected. Uisce Éireann (2023 notice)

Uisce Éireann (2022 notice)
151 2023 Drinking water County Tipperary, Ireland Raw water quality Due to the deterioration of raw water quality which had impacted the treatment processes at the local water treatment plant, Uisce Éireann (formerly Irish Water) and Tipperary County Council issued a Boil Water Notice on 27 July 2023 to consumers on the Burncourt Regional and Burncourt Ballylooby Public Water Supplies. The Notice later extended to customers on the Kiltankin and Clonmore South Group Water Schemes also, and remains in place as of 10 October 2023. More than 3,790 customers were affected. Uisce Éireann
152 2023 Drinking water County Wicklow, Ireland E.coli, enterococci, and coliforms Following the detection of elevated E.coli, enterococci, and coliforms in samples from the Knockanarrigan Davidstown Public Water Supply, a Boil Water Notice was issued on 2 October 2023 by Uisce Éireann (formerly Irish Water) and Wicklow County Council. The Notice remains in place as of mid-October 2023. Approximately 219 customers were affected. Uisce Éireann
153 2023 Drinking water County Roscommon, Ireland Disinfection issues Disinfection issues at the Longford Springs Water Treatment Plant led to the issuing of a Boil Water Notice by Uisce Éireann (formerly Irish Water) on 22 September 2023 to customers on the Castlerea Public Water Supply. The Notice was lifted after 2 weeks. Approximately 3,929 customers were affected. Uisce Éireann
154 2023 Drinking water O’Brien’s Bridge, Montpellier and Bridgetown, Ireland Disinfection issues An issue with disinfection at the local water treatment plant led to the issuing of a Boil Water Notice by Uisce Éireann (formerly Irish Water) and Clare County Council on 25 August 2023 to customers on the O’Brien’s Bridge Public Water Supply. The Notice remains in place as of mid-October 2023. Approximately 950 customers were affected. Uisce Éireann
155 2023 Drinking water County Clare, Ireland Chlorination Due to operational issues that have impacted chlorination at the local water treatment plant, Uisce Éireann (formerly Irish Water) and Clare County Council issued a Boil Water Notice to customers on the Killaloe Public Water Supply on 17 September 2023. The Notice remains in place as of mid-October 2023. Approximately 1,788 customers were affected. Uisce Éireann
156 2023 Drinking water County Kildare, Ireland Chlorination Due to an operational issue on the network impacting chlorine levels in the water supply in parts of North Kildare, Uisce Éireann (formerly Irish Water) and Kildare County Council issued a Boil Water Notice on 22 September 2023, which was lifted a week later. Approximately 3,557 customers were affected. Uisce Éireann
157 2023 Drinking water County Louth, Ireland Chlorination Operational issues impacting chlorination at the local water treatment plant led Uisce Éireann (formerly Irish Water) and Louth County Council to issue a Boil Water Notice on 4 September 2023 to all customers in the Ardee Water Supply Zone, which was lifted a week later. Approximately 8,064 customers were affected. Uisce Éireann
158 2023 Drinking water Kinvarra, County Galway, Ireland Disinfection issues Uisce Éireann (formerly Irish Water) issued a Boil Water Notice to customers on the Kinvara Public Water Supply on 9 October 2023 as a result of a mechanical issue at the local water treatment plant which compromised the disinfection of the water supply. Approximately 2,162 customers were affected. Uisce Éireann
159 2023 Drinking water Yarrabah, Queensland, Australia High copper levels Elevated levels of copper were detected in the tap water at an Aboriginal community health facility in far-north Queensland, leading to precautionary blood tests for staff and provision of bottled water to staff and visitors. Nil ABC News
160 2023 Drinking water Yarrabah, Queensland, Australia Elevated lead levels Elevated lead levels of up to 6 times the limit set in the World Health Organisation (WHO) guidelines were detected in the water supply at the new Clinical Services Building at Atherton Hospital in far-north Queensland, leading to several months of delay in the opening of the new facility.
Authorities were unsure of the source of the lead, but believed it was coming through the copper fittings.
Nil The Guardian
161 2023 Drinking water Yarrabah, Queensland, Australia Lead Lead was detected at several educational facilities in the Yarrabah region in far-north Queensland in June 2023, leading to authorities taking precautionary measures, including providing the children and staff with bottled water and free voluntary blood tests. Nil Queensland Health
162 2023 Drinking water Maranoa, Queensland, Australia Lead, copper and nickel Lead, copper and nickel were detected in the water supply and tapware of the Surat Multipurpose Health Service in south-western Queensland during a water quality audit at four facilities in August 2023. The levels of heavy metals detected were low, but still exceeded the levels specified in the Australian Drinking Water Guideline. The plumbing outlets at the affected facilities have been labelled “not for use” while authorities investigate the sources of contamination and determine what rectification works are required, if any. Nil Maranoa Today
163 2023 Sewage Nambucca Valley, NSW, Australia Sewage overflow Nambucca Valley Council experienced no fewer than 17 overflows from their sewage reticulation system that impacted the Nambucca River in the past two years, including three overflows between October 2022 and April 2023 alone. The problem is particularly acute during wet weather events as the sewage reticulation systems require significant assessment and capital works.
As a result, the NSW Environment Protection Agency (EPA) on 11 January 2023 updated the environment protection licence for Macksville Sewage Treatment Plant to include a Pollution Reduction Program (PRP), requiring Nambucca Valley Council to assess and repair the sewage reticulation system.
Council has commissioned an integrated water cycle management plan, which was expected to take 10-12 months to complete.
The EPA and Council also commenced an ongoing water quality monitoring program since 22 March 2023.
Spills from the sewerage overflows has cost the local oyster industry millions of dollars in economic losses. NSW Environment Protection Authority (EPA)

ABC News
164 2023 Drinking water HMAS Supply and HMAS Stalwart, Australian warships Plumbing defects Two Australian navy ships, HMAS Supply and HMAS Stalwart were commissioned in 2021 after being constructed by Spanish state-owned company Navantia at its Ferrol shipyard.
Water contamination issues linked to poor-quality plumbing were identified when the warships entered service, but the Government was only briefed about the issue two years later. As the Defence Industry Ministry and the Navy work to resolve the plumbing defects believed to be the source of the water contamination, sailors serving on board the ships are required to drink bottled water.
Nil ABC News
165 2023 Drinking water Wagga Wagga, NSW, Australia PFAS Low levels of per- and polyfluoroalkyl substances (PFASs), commonly known as “forever chemicals”, were detected in two groundwater monitoring wells just 650 metres from Wagga Wagga city’s main drinking water catchments. The chemical run-off from a nearby Air Force base was a known risk, however, the speed of the spread far exceeded the 50-year timeframe predicted by a 2021 modelling undertaken by the Defence Department. While Wagga Wagga's water utility, Riverina Water, said “there is no short-term risk of PFAS contamination to the bore field and the water is safe to drink”, the utility and the Defence Department both said they would be increasing monitoring. Nil
While “there is no short-term risk of PFAS contamination to the bore field and the water is safe to drink”, the incident highlights the importance of continuous monitoring and early detection as part of a preventive approach to the management of risks to drinking water quality.
ABC News
166 2023 Drinking water Zillah, Washington, USA E.coli Detection of E.coli bacteria in the water system led the Zillah Public Works Department to issue a Boil Water Advisory on 25 Oct 2023 to all residents and businesses in the City of Zillah in Washington State as a precautionary measure. Nil City of Zillah
167 2023 Recreational water The Promised Land, NSW, Australia Enterococci Bellingen Shire Council on the NSW Mid-North Coast advised swimmers to stay out of the Never Never River in the Promised Land area in January 2023 following detection of high levels of enterococci in the waters, indicating contamination by human and dog faecal matter. The Never Never River and the Promised Land are set within Tuckers Nob State Forest which, despite the area’s popularity with tourists, is not recognised as a tourist area by the Forestry Corporation of NSW and therefore does not have service facilities such as public toilets and rubbish bins. Nil ABC News
Bellingen Shire Council
168 2023 Recreational water Crossfield, Rocky View County, Alberta, Canada Faecal contamination Following a series of contamination incidents at the Banta Park splash park, the Town of Crossfield issued a public service announcement, urging visitors to the park to comply with the rules and not to use the water splash park for cleaning children or pets. The park’s water is recycled and treated like that of a pool. Nil Airdrie City View
169 2023 Recreational water Ipswich, QLD, Australia Cryptosporidium The hospitalisation of two children due to cryptosporidiosis raised health concerns. The Australian Centre for Disease Control narrowed the potential source of infection down to two recreational locations: the Orion Lagoon water park in Springfield and the Providence Ripley Splash N’Play Park. Water quality tests at Orion Lagoon showed no issues. However, a former disability support worker reportedly claimed that their clients often swam at the Springfield water park despite being incontinent and carrying infections. Two children (a 4 year-old and a 12 month-old) were hospitalised after contracting cryptosporidiosis. Springfield Lakes News
Courier Mail
170 2023 Recreational water Topeka, Kansas, USA Contamination The Blaisdell Family Aquatic Centre in the city of Topeka was temporarily closed on the 12th and 13th of July 2023 due to contamination in the water. Nil WIBW
171 2023 Drinking water San Mateo county, Pescadero, California, USA High levels of nitrate High levels of nitrate were detected in the drinking water supply at two San Mateo County schools in November 2023. Because of nitrate contamination, drinking faucets had been shut off and students had relied on shipments of bottled water for the past 25 years, but those shipments became unreliable. Nitrate is a fertilizer chemical known to contaminate drinking water in agricultural areas. Various solutions had been proposed to restore clean drinking water to the schools, but none had been implemented. Nil ABC7 news
172 2017 Recreational water Lake Macquarie, NSW, Australia Faecal contamination; chlorination “A child who was not toilet-trained used the pool without a correctly fitted aqua nappy" caused faecal contamination at the West Wallsend Swim Centre. Staff followed procedures to evacuate the pool, chemically treat the water and backwash the filtration equipment to remove pathogens. However, a pump failure led to the discharge of 16,000 litres of chlorinated water into a nearby creek.
The NSW Environment Protection Authority issued a $15,000 fine to Lake Macquarie Council for failing to properly maintain its pumping equipment.
Nil Sydney Morning Herald (SMH)
173 2023 Raw water The Netherlands PFAS The Dutch government is seeking to hold 3M Co responsible for polluting the Western Scheldt river with PFAS (aka forever chemicals) which allegedly resulted in financial damages for the fishing fleet and the government. Financial losses for the fishing industry Reuters
174 2023 Raw water The Netherlands Pesticides and other agricultural toxins A study by the Leiden Centre for Environmental Sciences (CML), commissioned by the not-for-profit organisation Natuur & Milieu, found “many highly toxic substances” in the water in the Netherlands. The study, which assessed the water quality in 153 recreational and nature areas in the Netherlands between 2014 and 2021, shows that the impact the Dutch agricultural and industrial sectors have had on the natural environment and water quality has led to a loss of biodiversity, damaged ecosystems and created health issues for local fauna. The study found traces of pesticides and other agricultural contaminants in 80% of the samples tested, with 40% of samples found to have levels exceeding environmental standards.
The Netherlands has previously been shown to have the worst water quality of all European Union member states, with only 1% of its waters assessed as “good”. Both groundwater and surface water in the country frequently contain agricultural contaminants such as high levels of fertilisers and residuals of pesticides. Large quantities of PFAS, microplastics and other micropollutants resulting from the production and use of medicines and cosmetics are another source of contamination. The Netherlands is working towards meeting the European Water Framework Directive by the 2027 deadline.
Loss of biodiversity, damaged ecosystems and health issues for local fauna I Am Expat
Wageningen University & Research
175 2023 Rainwater tanks Cadia Valley Operations, NSW, Australia Metals and sediments Dust emissions and air pollution issues at the Cadia gold mine in Central West NSW led to a series of investigations and legal actions by the NSW Environment Protection Authority (EPA) against the mine’s operator.
In March 2023, testing carried out by NSW Health found that contaminants in the local community’s tap water, including copper, lead, nickel and zinc, were within the Australian Drinking Water Guidelines (ADWG) health guideline values and the water was safe to drink. However, many residents in the area surrounding the Cadia mine rely on rainwater tanks for their domestic water supply. In response to community concerns, including detection of heavy metals in local residents’ blood samples, the EPA conducted water tank testing for 97 nearby residential properties that are rainwater dependant and found no significant relationship between the concentration of metals in the water and proximity to the mine.
The majority of results from kitchen tap samples showed metal concentrations below the ADWG health-based guideline values. At the small number of properties where lead or nickel levels in the samples collected from the kitchen tap marginally exceeded the health-based guideline value, the metal levels in the corresponding tank water samples from the same properties were within normal limits. Some water tank samples had levels of lead or cadmium or antimony above the health-based guideline values, but samples taken at the corresponding kitchen tap on these properties did not detect the same metals above the health-based guideline value. There were mixed results for aesthetic values in kitchen tap and tank water samples, with some outside the ranges set by the ADWG.
Tests of sediment samples taken from rainwater tanks showed metal concentrations largely within typical concentrations found in Australian tanks, with some exceptions. It is worth noting there are no relevant guideline values comparable to the sediment samples. The Australian and New Zealand sediment quality guidelines (ANZG 2018) are intended for the protection of aquatic ecosystems and livestock and are not suitable for the protection of human health, according to the EPA. In the absence of suitable guideline values, the EPA simply compared the concentration of metals in the samples collected to those measured in other parts of Australia.
Nil, although dozens of families had blood tests showing results of high levels of heavy metals such as lead, nickel and selenium. NSW Environment Protection Authority (EPA)
ABC News 8 Nov 2023
ABC News 22 May 2023
176 2022 Infection prevention and control Pennsylvania, USA Mycobacterium abscessus An outbreak of M. abscessus occurred at a paediatric facility in Pennsylvania in September 2022, affecting ventilator-dependent residents. Investigations revealed that the incident related to contaminated water and inadequate infection prevention and control practices. Notably, the facility did not have a water management plan. Extended periods of disuse of certain spaces in the building potentially resulted in stagnant water in plumbing, and the lack of a water management program meant that water quality was unmonitored. One case of clinical infection Centers for Disease Control and Prevention (CDC)
177 2023 Drinking water Falkirk, Scotland, UK Legionella Falkirk Council had experienced major problems reopening schools and nurseries after Legionella bacteria were found in the water supply at those premises after lockdown closures. A subsequent internal audit in June 2023 found that the procedures put in place to keep Legionella bacteria out of public water at council buildings were “unacceptable”, earning a “no assurance” rating. The audit identified serious shortcomings in the council’s procedures, including inconsistent checking and reporting regimes, a lack of training for staff, poor escalation of reporting, and inconsistency of checking pre-planned maintenance tasks carried out by contractors. Nil The Falkirk Herald
178 2023 Recreational water Olhão, Portugal Legionella Following the detection of Legionella bacteria in the municipal stadium swimming pool and changing rooms’ hot water system, Olhão City Council and local health authorities temporarily closed the entire pool complex. Nil Portugal Resident
179 2023 General water supply Nuneaton, Warwickshire, England, UK Legionella The planned opening of a new Nuneaton school building in November was delayed following the detection of traces of Legionella bacteria in parts of the school’s water system. Nil Coventry Live
180 2023 General water supply Rzeszów, Poland Legionella Legionella bacteria were found in the water supply system of the southeastern Polish city of Rzeszów, following an outbreak of Legionnaires’ disease in the country in August that led to multiple deaths. The source of the contamination remained uncertain and investigations were ongoing as of 11/09/2023. Routine disinfection of the city’s water supply was carried out while public fountains, public water sprays, and other public water sources were shut down temporarily. 23 deaths and 166 cases of infection confirmed between 18/08/2023 and 11/09/2023. World Health Organization (WHO)
181 2023 General water supply Milton Keynes, Buckinghamshire, England Legionella Legionella bacteria were detected during routine testing in parts of the water supply system at a local high school in Milton Keynes. The school advised that water fountains around the school were safe to drink from as they already had additional filtration in place, but non-essential water sources (e.g. sinks in classrooms and showers) were turned off as a precautionary measure. Nil MK Citizen
182 2023 General water supply Lancaster County, Pennsylvania, USA Legionella Following reports of a case of Legionnaires’ disease in August, Lancaster County Prison conducted tests for Legionella which returned positive results at multiple water sources at the facility. Disinfection measures were undertaken, yet further testing returned several positive results again. Fortunately, no inmates or staff tested positive for Legionnaires’ disease. 1 case of infection Lancaster Online
183 2023 General water supply New York City, USA Legionella Following reports of Legionnaires’ disease at a residential building complex in the Bronx in September, authorities performed tests and found Legionella bacteria in the water supply. The New York City Department of Health and Mental Hygiene advised residents to continue using the water but with certain guidelines. Multiple cases of infection PIX 11
185 2023 Operational risk Sydney, NSW, Australia Mix-up of fuel types At an Ampol service station located in North Ryde, the fuel tanks at their 98 unleaded petrol pumps were filled by the fuel distributor with diesel, during the week beginning 19 Nov 2023. While this example is not a direct link to water supply, it does highlight the importance of onsite management and receipt of chemicals. Unknown In the Cove
186 2023 Drinking water Carroll County, Virgina, USA Water leak The Carroll County Public Service Authority issued a boil water notice for the Cana area on 3 Dec 2023 after a water leak drained the tank in the area. It urged residents to boil all drinking water after water supply was restored. Nil 10 News
187 2022 Sewage Surrey, England, UK Storage of untreated sewage Between February and August 2022, after one of Thames Water’s sewage treatment works broke down and all of its other treatment plants had reached critical capacity, the company shipped more than 200 tankers (6,000 cubic metres) of raw sewage to a town in Surrey and left them in an open tank for six months (across the hottest summer on record) without being treated. Odour impacted around 11,000 residents The Guardian
188 2021-2022 Drinking water Washington, USA PFAS Tests by the US Department of Defense during 2021-2022 revealed that 866 private drinking water wells near military bases or other facilities in Washington (or nearly half of all wells tested in the state in the 2-year period) had been contaminated with PFAS. Unknown Seattle Times
189 2023 Drinking water England, UK PFAS PFAS (aka “forever chemicals”) were detected in 11,853 samples of raw and treated water from drinking water sources at 17 of 18 England’s water companies, according to the Drinking Water Inspectorate (DWI), the Guardian and Watershed Investigations. Unknown The Guardian
190 2023 Cybersecurity Aliquippa, Pennsylvania, USA OT-ICS security Iran-linked hacker group Cyber Av3ngers breached the Municipal Water Authority of Aliquippa by hacking into Internet-exposed programmable logic controllers (PLCs) used at one of its facilities.
PLCs are devices used to control and monitor various stages and processes of water and wastewater treatment. Hackers could manipulate compromised PLCs to contaminate water supply, such as by altering chemical dosing, or cause physical damage to the infrastructure by overloading pumps or opening and closing valves.
The CISA (Cybersecurity and Infrastructure Security Agency) stated that the hackers in this case “likely accessed the affected device — a Unitronics Vision Series PLC with a Human Machine Interface (HMI)—by exploiting cybersecurity weaknesses, including poor password security and exposure to the internet”.
Near miss – the attack did not compromise potable water safety for the served communities. US Cybersecurity & Infrastructure Security Agency (CISA)

Bleeping Computer

Cybersecurity Dive
191 2022 Infection prevention Napa County, California, USA Legionella An outbreak of Legionnaires disease occurred in Napa County, California in July 2022. Seven of the 11 environmental samples collected by investigators tested positive for Legionella. All positive samples were collected from a total of 7 facilities within 9 potential exposure sources (7 cooling towers, one decorative fountain, and one produce mister). One of the cooling towers was confirmed linked to at least two cases of infection. 17 identified cases of Legionnaires disease (14 confirmed and 3 suspected cases). Among the 17 cases, 16 patients were hospitalised, 10 were admitted to an ICU, and 5 required intubation and mechanical ventilation, and 1 patient died. US Centers for Disease Control and Prevention
192 2013 General water supply St. Bernard Parish, Louisiana, USA Naegleria fowleri In August 2013, a 4-year-old child died of primary amoebic meningoencephalitis (PAM), a rare but often fatal infection of the N. fowleri amoeba.
Investigations traced the source of the infection to tap water, in particular tap water that was used to supply water to a lawn water slide on which the child had played extensively before becoming ill. N. fowleri was identified in water samples from both the home where the child was staying and the local water distribution system.
This case was the first reported PAM death associated with culturable N. fowleri in tap water from a US treated drinking water system. It occurred in the context of an expanding geographic range for PAM beyond the country’s southern tier states. N. fowleri is a climate-sensitive, thermophilic amoeba, and PAM is a rare disease that is most often associated with swimming in warm untreated freshwater. This case and its association with tap water use highlights the evolving epidemiology of PAM and N. fowleri in the US and the importance of adequate disinfection throughout drinking water distribution systems.
1 death Clinical Infectious Diseases, Volume 60, Issue 8, 15 April 2015, Pages e36–e42
193 2023 Bottled water Strasbourg, France Unclean glass bottle Bottled drinking water supplied at the European Parliament’s premises in Strasbourg was suspected to have been contaminated – possibly from an unclean glass bottle – and caused several people to fall ill. Staffers and politicians received an emergency SMS, warning them not to drink from any water bottles in the building. Several cases of illness Politico
194 2019 Groundwater Northern Australia Burkholderia pseudomallei In the wet-dry tropics of Northern Australia, source water is often rich in iron-cycling bacteria, leading to excessive biofilm formation in pipes and promoting conditions for proliferation of opportunistic pathogen Burkholderia pseudomallei, the causative agent of the severe disease melioidosis in humans and animals.
B. pseudomallei is a natural component of the soil and surface water microbiota in rural Darwin, Northern Territory (northern Australia) and, in previous studies, 30% of tested unchlorinated residential water wells (bores) were positive for the bacteria. B. pseudomallei had previously been isolated from aerator sprays and tank sludge from water treatment plants and melioidosis cases and deaths due to contaminated drinking water have been documented in Northern Australia and Thailand.
Water can usually be made safe by treating with chlorine, but laboratory experiments have shown that some B. pseudomallei strains can tolerate higher chlorine levels.
In the present study, scientists assessed the microbial composition from the source to the distribution of three remote water supplies in the Northern Territory. They found that the geochemistry of the source groundwater had a substantial impact on the composition of the iron-cycling bacteria. B. pseudomallei was cultured from source water with low organic carbon but elevated iron levels and from a multi-species biofilm linked to iron bacteria. No B. pseudomallei were detected in treated water; however, abundant DNA of another opportunistic pathogen group, non-tuberculous mycobacteria, was recovered from treated parts of one water supply. This article provides sound evidence for ensuring that opportunistic pathogens remain on water suppliers’ radar, and the importance of fully understanding system risk, from source through to end use.
Nil Kaestli M, O’Donnell M, Rose A, Webb JR, Mayo M, Currie BJ, et al. (2019) Opportunistic pathogens and large microbial diversity detected in source-to-distribution drinking water of three remote communities in Northern Australia. PLoS Negl Trop Dis 13(9): e0007672.

The Conversation
195 2020 General water supply Melbourne, VIC, Australia Power outages Widespread power outages triggered by a severe storm in August 2020 led to disruption at Melbourne Water's Silvan water treatment plant, causing the chlorine disinfection process to go offline. This event resulted in approximately 100 ML of un-disinfected water from Silvan Reservoir entering the water supply system.
Boil Water Advisory Notifications were issued by the retailers Yarra Valley Water and South East Water, which were purchases of bulk water from the wholesaler, Melbourne Water.
Melbourne Water’s Incident Management Team worked closely with Yarra Valley Water, South East Water, and relevant state government agencies on a coordinated response to the incident. An extensive post-incident investigation was undertaken to identify the root cause as well as any opportunities for improvement.
The investigation found that both primary mains power (overhead and underground powerlines) as well as the emergency back-up diesel generator failed at the same time, a rare event and the second time it had occurred at Silvan water treatment plant in the last 20 years. The failures led to a disinfection outage lasting for approximately 7 hours.
It was also found that improved reporting and communication procedures and improved hydraulic modelling of the distribution network could have minimised delays in issuing the advisories and assisted in timely identification of affected customers.
More than 270,000 residents across nearly 100 suburbs in the eastern and northern parts of Melbourne were required to adhere to a boil water alerts for two days. Melbourne Water Annual Report 2020/21

Annual Report on Drinking Water Quality in Victoria 2020-21
196 2020-2021 General water supply Fujian Province, China Long-term stagnant water Stagnant water can cause water quality deterioration and, in particular, microbiological contamination/proliferation, posing potential health risks to occupants. Scientists in China conducted a field study of the microbiological quality of long-term stagnant water in university buildings that were unoccupied with little water usage during the COVID-19 pandemic.
The residual chlorine, turbidity, iron and zinc levels did not meet water quality guideline requirements , and the heterotrophic plate counts (HPC) exceeded the Chinese national standard by more than 100 times. It took 4-54 days for these parameters to recover to the routine levels. Six species of pathogens were detected with high frequency and levels (101-105 copies/100 mL). L. pneumophilia occurred in 91% of samples with turbidity > 1 NTU. Furthermore, a high concentration of endotoxin (>10 EU/mL) was found in long-term stagnant water, consistent with the high proportion of dead bacteria. The results provide strong evidence of increased microbiological risk, requiring more attention and implementation of an appropriate risk management plan, prior to reopening of buildings.
Nil Science of the Total Environment
Sci Total Environ. 2022 Feb 1; 806: 150616.
Published online 2021 Sep 27.
197 2023 Groundwater San Jerardo, California, USA Nitrate Some California farming communities have for many years faced issues with access to safe drinking water as the groundwater that feeds their wells has been contaminated with nitrates leached into the soil from years of large-scale farming.
Nitrate-laden drinking water can cause a blood disease known as blue baby syndrome in infants and affect pregnant women.
The Central Coast Regional Water Quality Control Board issued rules in 2021, limiting how much fertilizer farmers could apply. The state water board in 2023 put those plans on hold, arguing more consistent standards and scientific review are needed. As a result, residents of the San Jerardo cooperative and environmental organisations are now suing the state government, demanding stricter rules on how much fertilizer farmers can use. Farmers, meanwhile, filed their own legal action, claiming that neither the state nor the regional board had fully considered the economic impact of the rule change on farming operations.
Many residents in affected communities have had to rely on bottled drinking water, a significant economic burden that disproportionately affects low-income residents. Food Manufacturing
198 2023 Governance Portugal Falsification of data and analyses Law enforcement in Portugal arrested 20 individuals on 22 Nov 2023 as part of an investigation into the falsification of water analyses including water intended for human consumption, waste water, bathing water, swimming pools, catchments, streams, boreholes and wells.
The individuals arrested included employees and managers of a laboratory responsible for collecting and analysing water samples as well as employees, managers and local elected officials of municipal councils and/or management entities.
The Public Prosecutor’s Office alleged that the laboratory in question, in collusion with certain employees and elected official of the relevant municipal councils, “falsifies all the sampling procedures and analyses relating to the control of water for human consumption” contracted by those municipal councils.
The laboratory allegedly carried out the falsifications to “reduce costs” while putting public health and safety at risk.
Unknown Portugal Resident
Portugal Resident
199 2023-2024 Infection prevention Sydney, NSW, Australia Legionella NSW Health on 3 Jan 2024 issued a public health alert for people who visited the Sydney CBD area in December 2023 after seven people contracted Legionnaires’ disease (testing positive for the Legionella bacteria).
NSW Health environmental health officers were said to be working closely with the City of Sydney Council to inspect cooling towers, as a likely source of the Legionella bacteria (via aerosol generation and exposure).
As of 11 Jan 2014, 12 people have been diagnosed with Legionella pneumophila infection. NSW Health
The Medical Republic
200 2023 Drinking water Elmore, VIC, Australia Operational issue Coliban Water, the water supplier for the town of Elmore in northern Victoria, issued a Do Not Drink Tap Water Advisory on Christmas Day after a fault with the alarm system caused the Elmore Water Treatment Plant to stop running. The town’s clear water storage tank was drained as a result and the system experienced a pressure drop (leading to potential for contaminant ingress). Since boiling the water could not be relied on to remove all potential contaminants that might have entered the distribution system, affected residents had to rely on bottled drinking water for four days before the plant was restored to normal operations on 28 Dec 2023. Affected residents had to rely on bottled drinking water for four days. Local businesses suffered economic losses as some had closed during the period the tap water was unsafe for potable uses such as food preparation. Coliban Water
201 2024 Recreational water Sydney, NSW, Australia Sewage More than 20 beaches and pools across Sydney were declared unsuitable for swimming in January 2024 due to “possible” or “likely” contamination. The likely source of contamination was from recent heavy rainfall. It inundated drains and water mains with sewage contaminants, which subsequently overflowed into Sydney harbour and nearby beaches. Nil ABC News
202 2024 General water supply Kimberley, WA, Australia Thermophilic Naegleria, E. coli The water supplier owned by the Western Australian state government issued an alert on 12 Jan 2024, notifying the Ngumpan community to boil and cool water for drinking, playing and other uses due to the presence of thermophilic Naegleria and E. coli in their water supply.
An investigation was ongoing, but a Water Corporations spokesperson said that the contamination was likely due to a technical fault with the chlorinator on the community's supply.
Nil ABC News
203 1989 - 1990 Drinking water Cabool, Missouri, USA Escherichia coli O157 (bacterium) Waterborne contaminants (possibly from a concurrent sewer overflow) entered the distribution system through two major pipe breaks and 43service meter failures that occurred during unusually cold weather. The water utility did not practice disinfection following main repairs, relying instead on flushing the repaired main with finished water. 4 deaths;

243 patient studies as cases, 86 had bloody stools, 32 were hospitalized, 4 died, and 2 had haemolyticuremic syndrome (HUS)

Geldreich, E.E. (1996) Microbial Quality of Water Supply in Distribution Systems. Boca Raton, FL: Lewis Publishers.

Haas, C.N., R.B. Chitluru, M. Gupta, W.O. Pipes and G.A. Burlingame (1998) Development of Disinfection Guidelines for the Installation and Replacement of Water Mains. Denver, CO: AWWARF and AWWA.

Swerdlow DL, Woodruff BA, Brady RC, Griffin PM, Tippen S, Donnell HD Jr, Geldreich E, Payne BJ, Meyer A Jr, Wells JG, et al. (1992) A waterborne outbreak in Missouri of Escherichia coli O157:H7 associated with bloody diarrhea and death. Ann Intern Med. 1992 Nov 15;117(10):812-9.

USEPA (2002) New or Repaired Water Mains. Distribution System Issue Paper. August 15, 2002.
204 1993 Drinking water Gideon, Missouri, USA Salmonella spp (bacterium) Birds accessed distribution tank due to inadequate inspection and maintenance –flushing program caused water to turnover scouring sediments from the bottom of the tank. 44% of the 1,104 residents plus 28% of non-residents got ill Angulo, F.J., Tippen, S., Sharp, D.J., Payne, B.J., Collier, C., Hill, J.E., Barrett, T.J., Clark, R,M., Geldreich, E.E., Donnell, H.D. and Swerdlow, D.L. (1997) A community waterborne outbreak of salmonellosis and the effectiveness of a boil water order. American Journal of Public Health 87(4): 580-584.
Clark, R.M., Geldreich, E.E., Fox, K.R., Rice, E.W., Johnson, C.H., Goodrich, J.A., Barnick, J.A., Abdesaken, F. (1996) Tracking a Salmonella serovar typhimurium outbreak in Gideon, Missouri: Role of contaminant propagation modelling. Aqua - Journal of Water Supply: Research and Technology [AQUA J. WATER SUPPLY TECHNOL.]. Vol. 45, no. 4, pp. 171-183
Clark, R. (2000) Water quality modelling case studies. In: Water distribution systems handbook. Ed. Mays, L.W. McGraw Hill New York.
205 2005 Drinking Water Wales, UK Cryptosporidium (protozoan) Septic tanks, STP, sheep faeces insource water catchment. Oocysts found in raw and treated water but below the regulatory standard required of utilities in England and Wales i.e. 203 laboratory confirmed cases, several people hospitalised.
206 2011 Recycled water The Gap, QLD, Australia Fire Retardant In September2011, residents alerted Queensland Urban Utilities that foamy water was running from their taps. Previously Queensland Fire and Rescue had attended a house fire located on Dungory Street. How the foam had entered the distribution system was unknown. 387 houses were affected and provided with bottled water ABC News
207 2010 Recycled water Dandenong, Victoria, Australia Unknown A drinking fountain at Dandenong Park was connected to a recycled water tank for two years, providing users with potentially unsafe water to drink. The recycled water was only meant for flushing toilets, watering gardens and washing cars. No incidence of disease was noted, only that the drinking fountain water was yellow and a bit peculiar tasting Dandenong Leader
208 2006 - 2008 Recycled water Werribee Irrigation District, Melbourne, VIC, Australia Unknown In October 2006, stunted and discoloured lettuces were discovered in crops irrigated exclusively by recycled water on 13 properties. Stunted and yellowing crops were also discovered in April 2008.Thought to be caused by contaminated recycled water. Not stated but likely to have been many hundreds of thousands of dollars in damages. Melbourne News
209 2007 Recycled water Bangholme, VIC, Australia Pathogens An incident occurred at a new administration building at the Eastern Treatment Plant in Bangholme. Recycled water was inadvertently supplied to a drinking water tap, as a result of a cross connection, and 25 employees and contractors who had been using the building had been exposed to the recycled water for up to19 days. Several reported cases of gastro-intestinal illness The Age
210 2024 Sewage effluent Bullsbrook, WA, Australia Pathogens The Western Australian Department for Fire and Emergency Services used sewage wastewater to help extinguish an emergency level bushfire threatening the town of Bullsbrook and Bullsbrook College.
As a precaution, residents were warned not to eat anything from their gardens and to empty their water tanks.
Untreated sewage effluent contains a suite of human pathogens which can cause significant disease, especially in the immunocompromised and vulnerable.
The cause of the event was due to water being sourced from ponds that were not part of an exclusion zone:
“Our air attack supervisors have an extensive log of ‘no-go’ zones where they can’t draw water from and unfortunately, the two ponds that were drawn from yesterday, weren’t a part of that exclusion zone,”.
This event shows the importance of managing competing risk objectives, on one hand the protection of the community from the fire and on the other, public health protection from the quality of the water used for fire-fighting. A review of all water sources that can be used for firefighting will be conducted as a result of this incident. The event also underpins the importance of having a proactive approach to emergency management, including awareness sessions for staff and contractors, and key messaging to impacted stakeholders.
Bullsbrook Community College was closed for a day as a precaution. WA Today

The Guardian
211 2024 Public pools and water parks NSW, Australia Cryptosporidium Significant uptick in cryptosporidiosis, a diarrhoeal disease caused by the gut parasite, Cryptosporidium.
The disease is usually caught when people swim in or swallow water contaminated with the parasites. Inhaling contaminated water, can also be a source of infection, but is not as common.
Symptoms of cryptosporidiosis include acute diarrhoea, nausea, vomiting, fever, headache and loss of appetite.
The cause of the increase is not fully understood but may be weather-related.
Young children are particularly vulnerable.
Anyone who has the illness should stay away from public pools for at least two weeks.
498 recorded disease cases in NSW so far this year,
a nearly 500% increase from the previous five-year average (95 cases during the same time period).
ABC News

NSW Health
212 2024 Public pools and water parks Queensland, Australia Cryptosporidium Significant uptick in cryptosporidiosis, a diarrhoeal disease caused by the gut parasite, Cryptosporidium.
All Queensland regions have recorded a significant rise in cases.
Key environmental exposure areas include public pools, water parks and splash parks.
Young children are particularly vulnerable as the summer season poses a "perfect storm" of low immunity combined with extended heat.
More than 1,500 cases of cryptosporidiosis across Queensland so far this year (more than for the whole of 2023).
4,000% increase in Mackay and a 491% increase on the Darling Downs compared to the five-year average.
ABC News

Queensland Health
214 2024 Drinking water Grand Rapids, Minnesota, USA Legionnaires’ disease (bacterium) The source of a Legionnaires’ disease outbreak in Grand Rapids has been identified as the public water supply.
Critical sources of exposure to the disease are taps, showers, humidifiers and even hot tubs – essentially, anything that vapourises water that can then be inhaled.
The recommendation was that homeowners could address Legionella concerns by maintaining the hot water hot and the cold water cold and maintain a strict cleaning regime.
14 recorded cases of Legionnaires’ disease Lakeland PBS News
Lakeland PBS News

215 2019 Utilities North Carolina, USA Legionnaires’ disease (bacterium) Cases arose from people attending a State Fair in North Carolina, that had a hot spa displays, which were identified as the most likely outbreak source, making this the largest spa-associated
Legionnaires' disease outbreak globally.
Following the investigation, guidance on mitigating Legionella exposure from spa displays was released by public health authorities.
136 people were identified with fair-associated legionellosis, 98 were hospitalized and 4 died. Pub Med
216 2018-2019 Utilities Hot Springs, Arkansas, USA Legionnaires’ disease (bacterium) The abstract discusses Legionella pneumophila. Typically, Legionella thrives in warm, stagnant water lacking proper disinfection. However, Hot Springs National Park in Arkansas, USA, boasts naturally high water temperatures (>135°F), which historically prevented Legionella growth, and thus, the disease had not been linked to the park or other hot springs in the United States. Between 2018 and 2019, cases of Legionnaires' disease were reported in individuals who had visited the park. Three of these cases were linked to exposure in spa facilities that utilized untreated hot spring water. Environmental testing identified Legionella bacteria in piped spring water, including stagnant water at temperatures of 134°F. Five cases of Legionnaires' disease were reported in individuals who had visited the park. Three were linked to exposure in spa facilities. Pub Med
217 2023 Utilities Queenstown, NZ Cryptosporidium (protozoan) The paper discusses the response of the Queenstown Lakes District Council (QLDC) to a waterborne illness outbreak, Queenstown, NZ. As soon as it became apparent that the water supply could be the cause, QLDC issued a boil water notice, conducted sample collection, and cooperated with investigating agencies. The problem stemmed from the lack of a protozoa barrier at the Two Mile water treatment plant, despite it being deemed necessary since 1995. This failure to invest in drinking water infrastructure was also highlighted in the Havelock North waterborne illness outbreak in 2016. In response to such incidents, the government established Taumata Arowai, the national drinking water regulator. The paper details the urgent installation of UV disinfection systems by QLDC to address the issue.
The paper concludes by highlighting broader implications and actions, including the identification of other water supplies lacking necessary barriers and the requirement for plans and funding to rectify these deficiencies by specified deadlines.
Protozoa and other waterborne microorganisms can present a serious risk to public health, hence the importance of having a multi-barrier water treatment system.
The outbreak caused 66 confirmed and 20 probable cases, and a boiled water alert that lasted for 18 days.
There were also interruptions to local businesses, such as the temporary closure of a spa pool and swim class cancellations at other public pools.
Water Research Australia

Jim Graham, Cryptosporidium outbreak in Queenstown, New Zealand September 2023, Water Research Australia: WaterRA, HealthStream Issue 111, Mar 2024


Health NZ
Health NZ
218 2007 Drinking water Melbourne, VIC Australia gastro-intestinal illnesses A plumbing error at Melbourne Water's Eastern Treatment Plant’s (ETP) new administration building at Bangholme led to 14 staff members falling ill after drinking recycled water (not intended for human consumption). The issue occurred over nearly three weeks due to a misconnection of pipes, with the contaminated water reaching a tap designated for drinking water. The plant manager confirmed the incident was a result of a plumbing error and emphasized that recycled water, classified as "Class C," was not intended for drinking. In 2012, the ETP process train was improved, allowing production of a higher grade, Class A recycled water. 14 out of 25 Melbourne Water staff fell ill with gastro-intestinal illnesses The AGE


Melbourne Water Annual Report 2016-17
219 2016-2018 Utilities Wisconsin, USA Mycobacterium porcinum A Wisconsin hospital encountered a cluster of Mycobacterium porcinum isolates in respiratory cultures of intensive care unit patients between January and December 2017. Initially suspected as lab contamination, further investigation revealed M. porcinum contamination in hospital water sources, including ice machines and water dispensers. Protocol revisions were undertaken, including the use of tap water for respiratory cultures, leading to no new patient isolates of M. porcinum since June 2018. This highlights the importance of water management in hospitals to ensure patient safety during specimen collection and prevent misdiagnosis caused by the use of contaminated tap water. No associated clinical infections reported, only the cluster of isolates. CDC
220 1989 Drinking water Utah, USA Shiga toxin-producing Escherichia coli Utah recently upgraded its drinking water system, creating a new system for treated drinking water and repurposing the old one to supply untreated water for irrigation and firefighting.

Initially, residents understood the difference between the two water sources, with information likely becoming less certain over time, leading to confusion over end use suitability. This confusion led to an outbreak of life-threatening illnesses among children.

Outbreaks can be prevented by measures to avoid contamination in irrigation water, including treating the water, cleaning reservoirs, and covering them. Additionally, clearly labelling irrigation water and keeping residents informed about its dangers are crucial for preventing infections.
13 infected children, seven were hospitalized and two developed hemolytic uremic syndrome, a life-threatening complication that can lead to kidney failure. ars TECHNICA

Alert via Adrian Thompson
221 2024 Drinking water Mayotte Island Cholera Mayotte, is experiencing severe drinking water disruptions, with tap water only available two out of every three days due to the worst drought since 1997. The water crisis is exacerbated by poor infrastructure, inadequate investment, and pressure from illegal immigration from the Comoros. A recent cholera epidemic has worsened conditions. The spread of cholera has been attributed to long-standing failures in the water supply and sanitation systems. Many residents live in unsanitary conditions with limited water access. 76 people infected; 1 child death RFI
222 2024 Sewage Windermere, UK Raw sewage Millions of litres of raw sewage were illegally discharged into one of England's most famous lakes, due to a telecoms fault affecting a pumping station. The fault caused the main pumps to stop, leading emergency pumps to release untreated sewage into the lake for 10 hours. It was alleged that the utility failed to take timely and appropriate action to limit the amount of untreated pollution released. The utility also failed to report the incident to the Environment Agency until 13 hours after the event, contravening environmental regulations and also hindering effective investigation. Algal blooms, pathogens BBC

Alert via James Lucas, Edge Telemetrics
223 2024 Drinking water Brixham, Devon, UK Cryptosporidium (protozoan) A health alert occurred, due to numerous residents falling ill with suspected cryptosporidiosis (severe stomach pain and diarrhea, with symptoms lasting one to two weeks).

South West Water originally reported all water quality tests were clear.
However, local residents reported widespread illness, prompting concerns about water quality despite reassurances from authorities.

South West Water has since confirmed the likely cause of the event as a defective air valve, allowing ingress of contaminated water to their distribution system.
ocial media reports suggested "hundreds" were affected.

UK Health Security Agency confirmed 46 cases.
Manchester Evening News

Alert via Steve Atchison, Schedulista

BBC News
224 2024 Water supply Inverness, Nova Scotia, Canada Lack of Water Supply A water main break led to the municipality issuing a boil water advisory for its water utility customers.

Water supply was disrupted to the local hospital, who's emergency department stayed open, but non-emergency patients were advised to seek other care options. The hospital was left without running water for drinking or flushing toilets.
Several outpatient hospital services were cancelled, including renal dialysis, oncology treatments, and diagnostic imaging. CBS News
225 2024 Sewage Gold Coast, QLD, Australia Raw sewage A Gold Coast City Council is under investigation by the Queensland government following a major sewage spill (~350 ML raw sewage over three months) into the Albert River. The spill, caused by a broken pipe, went undetected until earlier this month.

The council is responsible for ensuring appropriate testing and monitoring of the Albert River and flow in waterways.

The Department of Environment is investigating the incident, considering potential prosecution for serious breach offences.
he council has initiated an independent investigation to determine the cause of the break and assess its response effectiveness. Ageing infrastructure and lack of upgrades are possible reasons for the failure.
Immediate and longer lasting public health and environmental impacts from sewage exposure. ABC News
226 2024 Bottled water Gard, (southern France) Faecal bacteria Following heavy rains associated with Storm Monica in mid-March, a well supplying water for the Perrier brand in Vergèze, near Nîmes, France, experienced a significant microbiological deviation. As a result, Nestlé, the parent company, has implemented reinforced surveillance at the well, as requested by authorities, and operations will resume under the authorities' control. Since April, Nestlé has intensified surveillance of its French drilling, and some wells were suspended in the Vosges last year. The French Senate initiated a parliamentary fact-finding mission on April 11 to investigate the government's oversight of bottled water manufacturers. Destruction of two million bottles of finished water product. Euronews
227 2024 Utilities Bakersfield, California, USA Arsenic, nitrate, and TCP Likely widespread problem of failing water systems (consistently failing to meet drinking water standards) in California, particularly in disadvantaged areas such as Kern County, affecting over a million residents.

The resilience of these systems is hindered by their small size and lack of economies of scale. While assistance has been sought from the city of Bakersfield, the overarching response has been consolidation of the smaller, failing utilities by the state water board. This process has been slow, with residents continuing to pay for water products and services which are not fit for purpose.
More than a million residents exposed to product that is failing to meet drinking water standards TKGET 17

228 2024 Utilities Pompano Beach, FLA, USA Legionella (bacterium) A lawsuit was filed against a condominium association who failed to maintain a jacuzzi, leading to a Legionnaire’s outbreak. The condominium association highlighted several actions which needed to be monitored and actioned, including closing the spa, changing filters, more frequent testing of the water, and hiring a consultant to oversee this. 1 Death 7 Miami News
Year Topic Location Contaminant / Issue Event Impact