The Hawke's Bay Regional Council is preparing to fine those from the Tukituki catchment who have not organised a Farm Environmental Management Plan (FEMP) by June 29.
The council has required properties of 4 hectares and over to show evidence of a FEMP or be in the line of fire for enforcement action under the Tukituki Plan (Plan Change 6).
Of the 1229 properties that need a FEMP, 253 land owners were yet to get one.
"Unfortunately, we will need to move to enforcement action or prosecution proceedings for those who don't act," said regulation manager Liz Lambert.
"We're not trying to ping people, we want them to do what is required but at the same time we won't let that situation go on forever."