Just before they retire, Sonoma County government employees can increase the amount they will get in their pensions by cashing out accrued leave, including vacation and holiday hours.

The practice is often referred to as "pension spiking."

It adds an average of 6.4 percent to public safety pensions in the county, and 4.2 percent for all other employees, retirement records show.

The average annual pension for a career public safety officer who retired in 2011 was about $94,500. The average for other workers was about $68,000.

Sonoma County's highest-paid officials add the most money to their final earnings through spiking moves, records show.

Rod Dole, the former auditor-controller-treasurer-tax collector, added $19,994, the most of any retiree in the past 12 years. Dole is the county's highest-paid pensioner, receiving $254,625 a year.

Below Dole, other former officials that added more than $18,500 to their final earnings — the figure on which pensions are computed — are: Randy Poole, the former Water Agency general manager; Mary Maddux-Gonzalez, the former public health officer; Bill Cogbill, the former sheriff; and Jo Weber, former director of the Human Services Department.

For the group, the cashouts boosted final earnings by 9 percent to 10 percent.

For the elected officials, Dole and Cogbill, the totals came through cashouts of administrative leave, a bonus they accrued throughout their career, up to 200 hours of which are pension-eligible.

Department heads and managers have a lower cap, allowing cashouts of up to 80 hours combined of administrative leave and vacation. They also get holidays and sick time, which can be converted to increase pensions.

For rank-and-file workers, the cashouts and conversions include up to 80 hours of vacation, 13 holidays, 17 hours of floating holidays and 24 hours of sick leave.

The caps are lower than in some other county pension systems in the state, where cashouts and other end-of-career moves alone can spike pensions by 30 percent.

Contra Costa County assumes cashouts and other "terminal pay" additions add an average of 12 percent to 16 percent for most of its employee groups, with the top average at 24 percent.

Two fire chiefs in that county system drew national media attention three years ago for spiking their final earnings and pensions by as much as 30 percent.

By comparison, the top spike in the past 12 years for Sonoma County was 20 percent, by Roy Loden, an investigator in the District Attorney's Office, who cashed out $17,123 in leave toward his final earnings.

Contra Costa County has since taken steps to limit such moves. But Bill Pollacek, the county's retired treasurer-tax collector, who served on its retirement board, still calls Contra Costa County "the pension spiking capital of the world."

"What's happening in your county is happening in virtually every other county in the state," he said. "Every system has its own way."