Janice Atkinson, Sonoma County's clerk, recorder, assessor and registrar of voters, has announced her plans to retire this summer.

Atkinson, 58, began her career in 1972 as a temporary elections clerk and is one of the longest serving employees in the county's workforce.

She will be 19 months into her second term in the elected Clerk-Recorder-Assessor's office when she steps down in July.

She has backed Ray Leonard, an administrative manager in the office, to be her successor for the remainder of the term. The decision is up to the Board of Supervisors.

Atkinson said her decision to step down was driven by the expected arrival of a grandchild and the completion of several county projects.

This year, those included electoral redistricting and the implementation of "top-two" elections, in which the two leading vote getters in a primary can face off against each other in a runoff, regardless of party affiliation.

The changes have redrawn political boundaries and scrambled county, state and national races.

"I get to go out with a bang," Atkinson said of the election season.

Atkinson played a lead role in the reorganization of California's election code in the mid-1990s and is recognized as an expert in state voter registration law.

"She's been a resource not only to our county but to all counties throughout California," said Sonoma County Administrator Veronica Ferguson, who called Atkinson's planned retirement "a tremendous loss."

When she retires, due to her 35 years of credited service, Atkinson will join the ranks of county pensioners earning more in retirement than they did while working.

Her 2011 pay included $167,274 in base wages and $15,762 in other earnings, including cash and car allowances. She also received nearly $83,000 in county-paid benefits.

Possible legislative and ballot-driven changes to public-sector pensions played a minor factor in her plans to retire, Atkinson said.

"We all watch that," she said, voicing some concern with changes that would affect current workers.

"I do think we have to honor the obligations that we have made to those who are working. That said, do I think there's room for pension reform? Yes I do."

Atkinson was a clerk-typist when she became a full-time county employee in 1976, the year her longtime predecessor Eeve Lewis was first elected to the clerk's office.

Outside of a stint working for Alameda and Contra Costa counties in 1985 and 1986, she has been with Sonoma County ever since. She served as assistant registrar of voters from 1996 to 2006, when she was was elected clerk-recorder-assessor replacing Lewis, who retired.

The office was consolidated from three elected positions in 2002. It supervises elections and voter registration, birth and death records, marriage licenses, property assessments, deed recording and a variety of other finance documents.

Atkinson was unopposed in her 2010 re-election.

A Santa Rosa native and Cloverdale resident, she has served since 1995 as the county's lead spokeswoman during disasters, a tenure that included several Russian River floods and the 1998 Rio Nido mudslide.

Her years in elected office encompassed the state's landmark legalization of gay marriage, the record turnout in the 2008 election and a historic economic and real estate downturn.

The resulting wave of property value reassessments, including a backlog now in the thousands, has been "difficult," Atkinson said.

"All in all, I've had a wonderful career," she said.

Her announcement comes amid a series of retirements and departures of top county leaders. Since late 2010, 11 of 26 department heads have either departed or announced their plans to step down in the coming months. In the later group are Public Defender John Abrahams, who is retiring next week, and Transportation and Public Works Director Phil Demery, who is set to step down this spring or summer.

Wendy Macy, the county's personnel director, called the turnover "significant," though she was not able to say whether it exceeded county averages.

"We have a huge generation change that's occurring," said Ferguson, the county administrator.

The Board of Supervisors is set to discuss Atkinson's interim replacement April 17.

You can reach Staff Writer Brett Wilkison at 521-5295 or brett.wilkison@pressdemocrat.com.