However, Busselton Water chiefs insist it is necessary, saying it is only a matter of time before the 300km network of pipes, servicing around 10,000 customers, create health problems.

And the Department of Health supports the decision.

“The implementation of chlorine is to manage the risk of the growing reticulation system,” Busselton Water chairman David Reid and CEO Keith White said in a joint statement.

“While the quality of water is as good as it ever was, the potential problem is within the growing network of pipes,” Mr Reid added.

“While we have not detected any serious health risk to date, professional advice suggests that the board cannot risk the community’s health.”

It is proposed to treat the water supply with chlorine in the next 12 months.

“It is our only option for a long-term solution,” Mr Reid said.

“Busselton Water has almost 300km of mains, which are increasing each year. Larger water volumes and satellite subdivisions are leading to a significant increase in the risk of harmful organism within the growing network.

“In October 2008 the board commissioned an investigation into Busselton Water’s disinfection system. Last month the board considered the final of a series of reports, which had five options.

“It found that as a result of our growing reticulation network that Busselton’s water was at risk of developing a water quality problem and because of that the board has made the decision to implement full-time chlorination.

“Currently water is treated through an ultraviolet (UV) disinfection process as it leaves the water treatment plant. This means that there is no residual disinfectant in the distribution network.

“None of the five options provided an adequate residual disinfection barrier, except full-time chlorination.

“The quality of the extracted water is as good as it ever was. The potential problem is within the growing network of pipes.