Incumbent Tim Cadogan will be challenged by first-term councillor Victoria Bonham. She is also standing for the council's Vincent ward and Vincent Community Board.
A flurry of other last-minute nominations means there will be elections in most wards and community boards.
They are the council Vincent ward, which has 11 nominations for five seats; Cromwell ward (five nominations for four seats); Cromwell Community Board (eight nominations for four seats); Maniototo Community Board (five nominations for four seats); Vincent Community Board (seven nominations for four seats); and Teviot Valley Community Board (five nominations for four seats).
Sitting councillors Stephen Jeffery (Teviot Valley ward) and Stu Duncan (Maniototo ward) have been elected unopposed.
The five members of Central Otago Health also become elected unopposed.
They are Britta Christensen (Cromwell ward), Caroline Tamblyn (Teviot Valley ward), Tracy Paterson and Robert Roy (Vincent ward) and Leigh Overton (Wanaka ward).
