That has upset at least one councillor.
In 2016, an ORC hearing committee chaired by Cr Gretchen Robertson set the Lindis' minimum flow at 900 litres per second.
However, in Environment Court mediation that followed, ORC staff accepted a proposal from irrigators, represented by the Lindis Catchment Group (LCG), of a minimum flow of 550 litres per second, with other changes in how the water was extracted from the river.
ORC chairman Stephen Woodhead yesterday said councillors were briefed twice but not asked to endorse the agreement reached by staff.
''Council has not made a formal decision on that. It wasn't put in front of them. It was agreed to by staff acting on our behalf.''
Asked if that was satisfactory, Cr Woodhead said ''that's something we will reflect on in due course, at the end of the [Environment Court] process.''
As a result of the change in position, the ORC is now backing the LCG's Environment Court appeal against the ORC's own original plan change 5A decision.
The Otago Fish & Game Council and about a dozen other groups are arguing in favour of the ORC's original decision.
Emails obtained by the Otago Daily Times show during the December 2016 to July 2017 mediation process some councillors were frustrated at not knowing what was happening.
In an email on July 11, [2017] Cr Graeme Bell asked Cr Woodhead for news of the mediation outcome.
''I have heard from various people different stories about the [mediation] decision.''
Cr Woodhead responded: ''I have heard a few rumours also ... things may still be confidential.''
Cr Bell then said an irrigator told him about it ''along with a number of other people in the agriculture world in different necks of the world [sic]''.
''I can't understand why we as councillors have not heard as yet.''
On August 1, [2017] Cr Ella Lawton said in an email to then ORC chief executive Peter Bodeker she had been contacted by members of the public.
''It is extremely disconcerting to have the public approach me with information that as a councillor I have not received from council.''
Mr Bodeker responded the matter was confidential to the parties ''and as such ORC cannot report details of the mediation to anyone other than immediate parties to the mediation''.
Cr Michael Laws said in an email to Mr Bodeker on August 1 it was his understanding the council was a party to the mediation.
Cr Bryan Scott joined the call for information in an email to Mr Bodeker on August 3, 2017.
He was concerned councillors had ''not been reasonably consulted'' and that ''some agreement has been reached that appears to have significant differences to the original hearing's outcome or intent''.
He asked that a copy of the ''agreement that has or was entered into'' be presented to councillors ''along with sufficient explanation and detail to be able to ascertain whether the agreement is reasonable or not''.
He suggested a new policy requiring councillors to endorse agreements where there was significant change.
Cr Robertson, who chaired the hearing that produced the ORC's original decision supported Cr Scott and endorsed his policy suggestion.
The change in the ORC's position became public on the first day of the Environment Court appeal hearing in Wanaka on November 7.
In his opening remarks, ORC lawyer Alistair Logan said only: ''Superficially, changes in the ORC position may seem surprising, but they are evidence-based.''
When approached for comment this week, Cr Scott said the matter was important, ''however I don't think right now when the Lindis is in the middle of a legal process is the best time to discuss''.
The Environment Court appeal hearing is due to resume on January 28.
