Bay of Plenty Regional Council is calling for landowners to protect the region's stopbanks from stock as the change of season comes in.
Rivers and drainage asset manager Kirsty Brown said most farmers and lifestyle block owners knew the rules but the importance of maintaining the region's flood defences could not be underestimated.
"Council manages and maintains almost 352km of stopbanks across the region to protect people, property and livelihoods.
"During winter, it is common sense to keep stock off the stopbanks as much as possible to prevent pugging and damage. Churned up ground is not just a surface problem, it can cause much greater issues."
She said good grass cover helped to "knit together" the soil, so anything that weakened that structure could lead to stopbank failure.
"Pigs and horses scraping and tearing up the grass cover can also be a potential problem and bulls are never permitted on stopbanks because their weight and behaviour can very quickly cause significant damage."
The Bay of Plenty Regional Council Flood Protection and Drainage Bylaw applied to drains, pumping stations, defences against water, river edge protection works and floodways managed by Council.
Under the bylaw it was an offense to damage stopbanks, and landowners can be held liable for any damage.
Rivers and drainage teams monitor the condition of stopbanks but any breaches could be reported to the council's pollution hotline.