THE future of the controversial Byrrill Creek Dam south-west of Murwillumbah is in doubt after Barry Longland, an opponent of the scheme, was yesterday elected Mayor in a surprise Tweed Shire Council vote.

Phil Youngblutt was elected Deputy Mayor in a move some saw as a deal worked out between the two men, who in the past have been at loggerheads on a number of issues.

Soon after the mayoral election, Cr Longland declared he expected the dam issue to come back to a meeting where he may be required to use his casting vote.

Outgoing mayor Kevin Skinner twice last year used his casting vote to push ahead with the controversial new dam after Liberal Party councillor Joan van Lieshout declined to vote because she and her husband Peter own land in the affected area.

Yesterday she said she had a "perceived" but not direct conflict of interest in the dam issue. Asked if she would take part in a future vote on the dam she replied: "I don't know."

But Cr van Lieshout attacked the process of councillors voting for a mayor every 12 months, after she backed Cr Skinner.

"It wasn't fair to the community because there are deals having to be done," she said.

Cr Youngblutt said he simply thought it was time Cr Longland was given a chance at the top job and for that reason did not vote for another mayoral contender, his long-time pro-development colleague Warren Polglase.

"Warren didn't have the numbers, so it was the way to go," Cr Youngblutt said.

Cr Longland admitted he and Cr Youngblutt had differences in the past, but added: "All of us have had differences over particular issues."

Cr Longland was supported by councillors Youngblutt, Dot Holdom and Greens councillor Katie Milne. Cr Skinner received only the support of Cr van Lieshout, while Cr Polglase was unable to garner any support.

Cr Longland then swung his support behind Cr Youngblutt for deputy mayor with other councillors, while Cr Skinner backed Cr van Lieshout for the job.

Cr Longland said he would "anxiously await" a State Government review into a government ban on building the Byrrill Creek Dam and then expected the issue "to come back to council".

"I will be agitating to have that review completed as quickly as possible," he said.