It is understood a byelection, which could cost ratepayers up to $100,000, will be held within the next 90 days.

Cr Maher's resignation is the second in less than a week within the council with its group manager of facilities and services, Mike Trigar, also choosing to part company.

While Cr Maher citied family obligations as the official reason for his resignation, it is understood a row over the council's involvement with a private sand mining company owned by Cr MacKenzie also contributed to the decision.

One councillor told the Examiner Cr Maher, who had been a part of Cr MacKenzie's liberal voting faction 'the Magnificent Seven', had for some time wanted to distance himself from Cr MacKenzie and the recent dispute had been the last straw.

"A conversation was held between the councillors and general manager Peter Gesling moments before the meeting [March 23]," the councillor said.

"He told us in regard to the notice of motion that we should vote to go away and negotiate with the family over an alternative road deviation and have the matter come back before council to be dealt with, but we said he could go to hell."

"I believe that was the straw that broke the camel's back."

The claim has been backed up by another councillor.

Mr Gesling refuted the claims however, saying he had not pressured any of the councillors.

"I reject completely the fact that I pressured anyone," he said.

"I explained the reasons behind the recommendations seen in the report and supported it, but I didn't pressure any councillors in any way."

The byelection is expected to draw a number of candidates as the new councillor would be seen to hold the balance of power with Cr MacKenzie's support group now down one member. However, Cr MacKenzie said he was not concerned over future change. He said should the numbers be tied six-six on an issue he would use his casting vote as the deciding factor. Cr Maher did not return calls from the Examiner about his resignation. At the 2008 local government poll Cr Maher had been a surprise election after running on a ticket with his brother-in-law Ken Jordan.