But restructuring required flexibility to shuffle employees, and minimum staffing was blocking any significant changes.

The associations agreed to consider eliminating minimum staffing in the second round of negotiations, Mensinger said.

In exchange, they told the council they wanted pay security — no deductions or raises until 2017.

"I think they understand that they're well-paid," Mensinger said. "They all get it."

Also, the council agreed to pay some fringe benefits that Righeimer and other leaders criticized in the past as exorbitant.

In one, the administration counts some retirement fund payments toward the firefighters' compensation, thus inflating the final salary number used in pension calculations. Another allows employees to bank their unused sick leave. Also, current firefighters get to keep their retirement benefits, which allow them to retire at age 50 with up to 90% of their compensation after working 30 years.

"It was really important to get the minimum manning down, so we had to give on something," Righeimer said.

During the final two rounds of negotiations, Arnold presented his restructuring plan to both sides: shift resources to more effectively respond to medical emergencies, close a fire station, eliminate some vacant positions and buy new ambulances.

If all goes as planned, it could save millions, he said.

"It was kind of a long, drawn-out process, but it took awhile to get to the point where we agreed with the city," Vasin said. "For us, it took some time to build a level of trust."

With the November election approaching, Mensinger hopes the firefighter associations don't spend money campaigning against him and Councilman Gary Monahan, as they have both been targeted by organized labor in the past.

But Mensinger and Righeimer denied there being any agreements between their camp and the firefighters' associations to stay out of the election.

Even the council's critics praised the deal, although they were wary of cutting too much.

"I'm just a little concerned that with the number of staffing that there's going to be now if the response times are going to be as good," said Robin Leffler, president of Costa Mesans for Responsible Government. "I hope they are."

After resting his reputation on the response data, Arnold said he plans to lead the transition and stay on for two to three years.

"It's my community. I love it, I live here," he said. "I want to contribute, and that's what I'm doing."

mike.reicher@latimes.com; lauren.williams@latimes.com

Twitter: @mreicher and @lawilliams30