The group sent a letter to all councillors and the chief executive officer Peter Schneider on Monday which detailed allegations made by council staff about use of credit cards and invoices.

President Dean Hurlston said he was surprised they had been approached by "several staff" and he had encouraged them to take their complaints to the Independent Broad-based Anti-corruption Committee, the Victorian ombudsman or the Local Government Inspectorate.

"They're risking their jobs to actually try and get this information out and get someone to determine it, from what I'm hearing they're frustrated that council just keeps trying to dodge the issue rather than get it all on the table, deal with it, let people grieve, heal and move on," he said.

Despite three investigations being under way into the council - an internal and external audit and an inquiry by the ombudsman - Mr Hurlston said they didn't go far enough.

The Local Government Inspectorate is also assessing matters related to the council and will decide by the end of the month whether an investigation is warranted.

Despite the council asking Local Government Minister Adem Somyurek to step in and investigate its financial management, financial performance and governance over the past seven years, he said he would not intervene while the reviews were under way.

An IBAC spokesman said that for legal and operational reasons, it generally did not comment whether it had a complaint or investigation before it.

The council said that if it was to refer matters to an authority such as IBAC, there were strict protocols which would prevent it from engaging in commentary.

In responding to the letter, Cr Mike Neoh, who is one of two councillors on the audit committee which also includes Cr Sue Cassidy and three independent members, said the scope of the external audit already addressed the issues raised.

"The points raised and requests are obsolete because we (the audit committee) have appointed an external auditor where all these issues are already in the scope," Cr Neoh said.

Mr Hurlston said the audit looked at a very narrow brief of council expenditure. "We're saying all staff expenditure must be looked at for at least three to five years," he said.

"Every bit of authorised expenditure by staff must be checked.

"What will happen is an ombudsman or an inspectorate will come in and have a broadbrush, they'll come in for a day or two and they'll have a quick look at all of the documentation."

Mr Hurlson said Ratepayers Victoria said it was perhaps more appropriate for IBAC to actually take over and give a full scope of investigation and direct council a little bit more.

"What we're concerned about is there's 79 councils in Melbourne, there's a lot going on, Warrnambool's getting too much attention and it's not going away and the reason it's not going away is because it's not being dealt with adequately," he said.

"This isn't the first time it's happened in a council, but it's the longest I've seen the issue resonating in the community unresolved."

The council's chief executive officer Peter Schneider said that over recent months staff had been made aware of the channels through which they could voice any workplace concerns.

"None of the allegations raised in the letter from Ratepayers Victoria have been reported to me in the past seven months," he said.

"Those who have concerns are encouraged to take action - either through their manager, director, myself or external referral agencies.

"We are implementing a new workplace culture and values program that will help ensure we are delivering effective and efficient customer-focused services to the community."

When asked if the council was looking into staff leaking information about credit card and invoice spending, it said matters relation to staff were confidential and it was not appropriate to make any comment.

Mr Hulston said the allegations made by staff were just that, allegations, that hadn't been proven.