He said this ''defied belief'', as the road was a well-known, picturesque ''gateway to Central Otago and Queenstown'' that was much photographed by visitors.
The board and council have both voted to endorse the ''strongly worded email'' Cadogan was sending ORC chairman Stephen Woodhead, ORC technical committee chairman Andrew Noone and Otago Regional Transport Committee chairman Trevor Kempton about the issue.
It would say that the ORC might be ''correct in law'' that it did not need district council permission to build the site where it wanted to, but ''it would be a terrible mistake [to build it without CODC approval] ... at every other level'', Cadogan said.
The matter was also discussed at yesterday's full council meeting.
Roading committee chairman Dr Barrie Wills said it continued to be a ''no-brainer'' that the Ripponvale site was unsuitable.
The CODC favoured an alternative site near Tarras, he said.
Wills said the ORC's technical committee would be discussing the issue today.
Kempton said he was unable to comment about the issue until after today's committee meeting.