The Hawke's Bay Regional Council will get another chance to vote on whether to invest in the Ruataniwha Dam.
Councillors had a motion before them to invest $80 million of ratepayers' money in the dam, which passed by six votes to three at a meeting on Wednesday.
Councillor Peter Beaven successfully moved an amendment that a final decision on investing in the dam must be subject to councillors being satisified with the business case.
Mr Beaven said he supported the motion because the final decision now rests with councillors as a result of that amendment and they will get another vote.
Council chief executive Liz Lambert said it may be months before a recommendation on investing is known due to legal challenges against the board of inquiry's final decision, due by Friday.
Councillor Rex Graham voted against the proposal, saying the council was asking him to jump of Te Mata Peak without a parachute, and said it had been a litany of poor process.