The historic vote will take place at the club on Tuesday night.

OCBC secretary manager Neil Southcombe said it was likely to be close.

"It's fairly evenly split from what I've seen and heard," he said.

Mr Southcombe said he could not say which issues the members were concerned about.

"There's not really a definite [indication] of what people are saying. It's very close," he said.

Mr Southcombe said the club had 121 years of history and its Warrendine Street premises was its third location.

He said the meeting would also have to consider declaring the building was not core property of the club.

Under the memorandum of understanding prepared by the two clubs for a potential amalgamation the OCBC building would continue to operate for at least five years.

Mr Southcombe said if the members voted 'yes' to the amalgamation OESC members would meet at their club on Wednesday night to also vote on the amalgamation.

OESC CEO Daniel Perkiss said the club's board and management had consulted with "all key interest groups" about the plans.

"There are mixed feelings particularly from some members of OCBC which is understandable," he said.

"Ultimately we have laid down a very comprehensive and detailed plan. We genuinely believe this will underpin the game of bowls for generations to come."

"Given the demonstrated history of losses that OCBC has incurred over the past decade we do fear for the future of this community asset if a 'yes' vote is not carried.

He said OESC was encouraging a 'yes' vote for both clubs' meetings.

Mr Perkiss said if a 'no' vote occurred the club would continue plans to develop a sports facility at Wentworth Golf Club, which amalgamated with OESC last year.

"We will happily move on and begin the design process of our new sporting home at Wentworth which will still include two bowling greens and a state-of-the-art facility," he said.

"Under either outcome the members of OESC are winners with an exciting development on the way."