The council has since been taking a "zero tolerance" approach to the practice - working to ensure farmers are aware of the rules of operating feedlots.
Farmers were also given time to remedy any issues, and obtain a resource consent if needed. If feedlots do not meet RRMP rules a consent is required, and they are monitored to ensure they meet the conditions of this consent.
It appears this move has sparked a change among farmers. Federated Farmers Hawke's Bay provincial president Will Foley said this "learning experience" made farmers more conscious about what possible effects their operations were having on the environment.
"Whether its feedlots or something else within the farming business, farmers are thinking about what are they doing and what environmental impact is it having and what can - or should - I do to reduce any impact," he said.
"I think there's been a good culture shift among farmers about accepting and understanding ... what can we do about it now. There's been lots of work done already but we know there's still heaps to go."
As well as engaging with catchment-wide environmental plans, Mr Foley said he thought farmers had been very receptive with changes the regional council had been making to the monitoring of feedlots.
With feedlots being a winter activity - used to keep cattle well fed, and pastures in good condition - Mr Foley said this season would be a good test of how prepared the council was in its stocktake of feedlots.
Council Compliance Manager Wayne Wright said this winter their compliance team would be undertaking flyovers to ensure farmers were following the feedlot rules.
"Any farmers operating feedlots outside the rules this winter will need to remedy the situation immediately or could face prosecution," he said.
The compliance team would act against operators where effluent was seen to flow overland to a waterway, he said.
The improved awareness of feedlot rules were thought to have led to the council receiving
nine applications for resource consent for feedlots this year.
Earlier this week the council received an update on feedlot activities and management.
A paper before council noted there had previously been two feedlots consented in Hawke's Bay, and nine feedlots known to be operating last year.
One feedpad had permits which consented the discharge of effluent collected from the feedpad.
Last winter, Mr Foley said he thought there would be only be around 10 large-scale feedlot operations in Central Hawke's Bay.
Due to their high cost, only a minority of farmers are thought to use feedlots.