Police are appealing for witnesses to come forward after holes were drilled into a section of pipeline on the Mid North Coast.
Police said contractors noticed a large number of small holes along about 2km of pipeline near a water treatment plant at Elliots Road, Nabiac, about 2pm on Monday.
Officers from Manning-Great Lakes Police District attended and began an investigation.
It's estimated the damage will cost more than $150,000 to repair.
Police believe the damage occurred between Sunday night (January 12) and Monday morning (January 13).
Anyone who saw or heard anything suspicious in the area during that evening, or who may have information that could assist detectives, can contact Crime Stoppers on 1800 333 000.
