Cr Vanessa Van Uden said she had not wanted it to be a public-excluded meeting but was outvoted by a majority of councillors because some of the information was commercially sensitive.
She said Crs Cath Gilmour and Lyal Cocks had supported her in voting for an open meeting, against the recommendations of council staff.
Cr Van Uden, along with Crs Gilmour, Cocks and Mel Gazzard, had called for yesterday's extraordinary council meeting because they wanted details of the contract aired before the August 1 deadline for signing it.
She said council staff had showed "utter contempt" for councillors by ignoring her requests since February for the contract to be presented to the council's utilities committee.
"I didn't want us to be presented with a fait accompli. We can't just rubber-stamp something without fully understanding it," she said.
Yesterday's meeting was to have involved discussion on what form the contract would take, but council staff had included financial information on the contract's tendering negotiations in the agenda.
She had asked for those financial details to be removed so the meeting could progress in public but was told by staff this was not possible.
Cr Van Uden could not reveal details of what was discussed yesterday but said the meeting "went well".
She said the meeting was essential to ensure problems with the United Water contract, signed last year, were not repeated.
"In order for us to sign off on this type of contract again, the councillors need to fully understand the benefits and costs," she said.
She said council was facing a $1.1 million overspend on call-outs for water leaks. an excess that might not have happened if council had been fully informed.
Council chief executive Duncan Field said the roading contract was still under negotiation.
Councillors were given an update on those negotiations including financial details and what form the contract would take.
He said a statement on the contract would be released today and "large parts" of a report from the meeting would be available.
