Waikato Regional Council is warning agricultural contractors it will take enforcement action against those who ignore rules on maize growing.
Contractors are meant to leave a two metre buffer zone between waterways and areas cultivated for maize to keep sediment and nutrients out of the water.
The council says it has been getting reports that some are failing to follow the two-metre rule during spring ploughing and sowing.
It has written to all agricultural contractors in the region to remind them.
