A study into Queensland’s water quality supply aims to determine what changes could be made to reduce the risk of future legionella outbreaks.
Queensland Health has put out to tender for a specialist contractor to undertake the study, which will examine water quality at a number of sites around the state.
The study was one of the recommendations from a review conducted after last year’s legionella outbreak at the Wesley Hospital.
A 68-year-old man died and a 46-year-old woman was left critically ill after becoming infected in June 2013, forcing the hospital offline and sparking a statewide testing regime.
Queensland Health Director of Water Greg Jackson said that outbreak was traced to the drinking water supply.
“There were aspects to the plumbing in the Wesley Hospital that encouraged the growth of legionella that led to the exposure,” he said.
“The reality is that legionella doesn’t make most people sick… it’s only really the immune-comprised, those who are sick from something else, who are vulnerable.”
Mr Jackson said the study would provide a more robust, system-wide risk management approach that could be passed to local water supply managers such as councils.
“We’re not saying that the hospital has to do all the work to control legionella,” he said.
“We’re looking at whether there are some aspects of the incoming water that could either make it harder or easier to control legionella in the hospital.”
Mr Jackson said that as an example legionella often relied on organic carbon dissolved in the drinking water to grow.
“If a council can reduce the level of carbon in their water supply, maybe through an extra treatment step, that could make it harder for legionella to grow,” he said.
“The same goes for chlorine, if they can ensure the chlorine residual is still at a good level by the time it gets to the hospital, that will make it easier for the hospital to maintain the safety of drinking water.”
Mr Jackson said Queenslanders should generally have confidence in the safety of the state’s water supply.
“If there was something wrong with it, I’d know about it,” he said.
“My children drink tap water.”