The Water Corporation reported the incident to police, who are investigating.
Water Corporation Great Southern regional manager John Janssen said this vandalism would not result in water restrictions being imposed in Waroona.
“Waroona is supplied with water from the Integrated Water Supply Scheme (IWSS) which supplies water to around two million people in Perth, Mandurah, parts of the South-West and through the Goldfields, and Agricultural Water Supply Scheme,” he said.
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READ NOW“Water for the IWSS is sourced from dams, groundwater and desalination.
“Waroona is subject to the permanent two-day-per-week sprinkler roster throughout spring, summer and autumn.”
Samson Pipehead Dam is a smaller dam, which mainly holds water from the larger Samson Dam for environmental release.
Mr Janssen said vandalism at dams which results in a release of water is extremely rare.
“Criminal vandalism of water infrastructure is always a concern, especially when it wastes precious water,” Mr Janssen said.
“We are extremely disappointed in the damage to the dam and the resulting loss of water.
“We always ask people to contact police immediately if they see any suspicious activity near one of our assets.”