The Taranaki Regional Council claimed vandals who attacked a flood monitoring station this week put people's lives and livelihoods at risk.
Director of environmental quality Abby Matthews said council hydrology officers discovered a small fire had been lit under one monitoring station, when undertaking routine checks on the network in the Upper Waitōtara catchment.
She said the stations send out automated phone alerts when rivers reach dangerous levels and are vitally important.
"What they've done has actually put people's lives and well-being at risk, so we take that very seriously and our sites and the work we do is critical to the well-being of people in our community.
"Obviously without that site operating if we had a flood we'd be in quite a lot of trouble and wouldn't necessarily know what was going on."
Council science manager hydrology/biology Regan Phipps said the monitoring stations were important for letting farmers know they should move stock or take other precautions. They also warned communities and roading contractors when road access may be at risk.
"Our flood monitoring networks are hugely important, so we were gutted to find that vandals had been at work. This vandalism is a huge disservice to those communities."
Phipps said anyone who saw people tampering with monitoring equipment should call the police immediately.
The regional council operates 22 flood-warning stations across Taranaki, with the key ones being in the Waitōtara River, Waiwhakaiho River and Waitara River catchments.
They are among its 62 automated environmental monitoring sites across the region, all of which feed data to the TRC website.
Matthews said temporary repairs had been made to the damaged Waitōtara monitoring station, but it would not be fully operational for a couple of weeks.
RNZ
