Mr Foster said the council had spent no more than $5000 on legal advice after one official complaint and "a number of inquiries" from the public asking if the signs were legal.
The advice was some of the signs did not comply with the rules under the District Plan, he said. "It comes down to community safety and the amenity of neighbourhoods. We act on a community inquiry and feedback basis. There has been a huge amount of public interest in this issue ... and we've had people pushing us for a response. So we needed to look at this and see what was going on."
He said there were two types of signs - temporary signs advertising things such as community events, galas and concerts, that were allowed to be up for six weeks. The other was permanent signs which are governed by a number of different bylaws.
However, the signs involved are on private property and come under the District Plan, he said.
The council's resource management compliance officer Kurt Williams said the council was looking at the size of the signs, "whether they were genuinely temporary in nature" and their location.
He said property owners with possible non-compliant signage would be given the opportunity to remove them or apply for resource consent.
He said signs on state highways, such as ones on Old Taupo Rd and Ngongotaha Rd, fell under New Zealand Transport Agency rules.
Mr Foster said the council would not be heavy handed and would give property owners plenty of time to digest the information.
He said if owners did not comply they would be sent an abatement notice under the District Plan.
District councillor and chairwoman of Rotorua District Residents and Ratepayers Glenys Searancke said she thought the move was a waste of ratepayers' money and the time of council staff.
"We believe they are temporary signs and the debatable point is that the messages they carry change every three or four weeks.
"I think it's petty, it's done in many different cities in New Zealand. What we are doing it for is to create interest in local government and that there is an election next year.
"As far as I'm concerned it will be up to the individual property owner to remove them or not. If the people whose fence or land they are on wants them gone we will take them down," she said.
"If they don't want to do that then we will see what happens."