Almost $100,000 of damage has been caused by break-ins at Western Water reservoirs and storage tank reserves in the past few months.
The water company is urging people to be on the lookout after intruders damaged fences to gain entry to some sites.
Water systems and solutions acting manager Rod Curtis said the incidents had been reported to police, but they are unsure why the reservoirs and tank areas are being targeted.
Each break-in has cost Wester Water $20,000 to repair the fences, $5000 to test the water quality and an additional $5000 for manpower, Mr Curtis said.
He said the organisation needs to be hypervigilant after each break-in and ensure the water has not been contaminated.
“We have to commit a huge amount of resources to understand if the water is safe … you can never know for sure before testing it out,” he said.
“Even a small breach of the fences can escalate the situation.”
People found guilty of entering drinking water storage areas face fines of up to $9300, or six months’ imprisonment for a first offence.
Western Water will increase security measures at its sites, but Mr Curtis has urged people to stay out.
“These assets are providing water to the community, and if tanks have to be taken offline, there are huge ramifications,” he said. “This includes water outages or notices.
“It’s important, if people have seen something, to say something.”
