A sign for No on Measure Z is seen at Yorktown Avenue and Goldenwest Street in Huntington Beach. (KEVIN CHANG, HB Independent / September 18, 2012)

Save Our HB members walked en masse at midnight Monday to make known their opposition to a ballot initiative that would repeal a special property tax.

The tax helps fund the retirements of public safety employees. Measure Z on the November ballot would repeal it.

Monday was the first day campaign signs could legally be posted, and the grass-roots group wanted to be first.

"We got the prime spots before any other candidate got them," said Councilman Keith Bohr, who is leading the opposition effort with council members Connie Boardman, Joe Shaw.

Thirty teams of two, including former mayors and community members, posted hundreds of 4-by-8-foot "No New Taxes. No on Z" signs with their website, http://www.saveourhb.com.

The pre-1978 public safety employee retirement tax levies a penny and a half on every $100 of assessed property value, or $15 per $100,000.

The tax brings in about $4.2 million a year, which helps pay police and firefighter pensions.

Mayor Don Hansen and resident Frank Morrell, who authored the measure, gathered the signatures to put Measure Z on the ballot and are working to see it pass.

Hansen said that he and other supporters of the measure are planning an aggressive outreach campaign. A website, yesonmeasurez.com, was launched Wednesday.

Opponents of the measure say Hansen voted in 2005, 2006 and 2010 to increase the tax, but now he wants people to believe he's against it.

Hansen said the economy was better then and that he never voted to up the tax.

A review of a 2010 City Council meeting video shows Hansen opposed to increasing but in favor of maintaining the tax.

Asked why he didn't vote against maintaining the tax he said that at the time there was no plan on how to make up for the lost revenue, but there is one now.

Hansen said the employee contracts are about to expire, and repealing the tax will force employee unions to pay their full share — something he thinks can be collectively bargained.

"Either way ... it's the failure of the unions to embrace real reform," he said.

The city will continue to be responsible for the employee benefits and ending the tax does not automatically mean employee groups are obligated to contribute more to their pensions because the contributions are not required in their contracts.

However, the city could always bargain for additional pension contributions with the police and firefighter associations in the future.

Police and fire have gradually increased their pension contributions, and the goal is for them to pay their full share within two years, according to city officials.

Repealing the tax now could lead to more layoffs, the elimination of the crime scene investigation unit and the Fire Department's hazardous materials response team, the closure of two branch libraries and a reduction in the hours of the Central Library, Bohr said.

"The timing is terrible," Bohr said, adding that the current budget challengers are already deep. "It's going to eliminate $4.2 million, and it does nothing to lessen our current obligations."

Even if the employees pay their full share, repealing the property tax will still leave Huntington Beach with $1.7 million, Bohr said.

"It's disingenuous to say this is pension reform," Bohr said.

Former Mayor Shirley Dettloff said residents are the ones who will suffer the consequences if the measure passes.

"I just think that if you want pension reform, you do it in the proper way, and as far as I'm concerned, that is through negotiations," she said.

mona.shadia@latimes.com

Twitter: @MonaShadia