Mr Bowen said the council wanted to understand how groups thought the implementation was going and what required further attention.
"Depending on what the evaluation project finds we may make improvements to our approach to implementation of the plan, or council may decide to look at ways in which the plan itself could be improved," he said.
"It will not result directly in changes to the One Plan. At most it may identify that a plan change should be considered."
The Chronicle revealed this month that 40 per cent of farms which were required to lodge a resource consent by January 1 had not.
The council has also been granting discretionary consent for farms to leach nitrogen at up to three times the One Plan limit. But Horizons have put his down to changes on the Overseer model used to estimate nitrogen leaching.
Regardless of the feedback, Mr Bowen said Horizons would be required to make amendments to the One Plan over the next few years to incorporate aspects of the National Policy Statement for Freshwater Management 2014.