The County Council approved the appointment Monday with a 5-0 vote.
Trenary, 47, of Stanwood, is a captain at the sheriff's office, where he's worked since 1991.
He served as police chief for Stanwood, which contracts with the county for police services, from 2008 to 2012.
Trenary, a former leader of the union that represents sheriff's deputies, also has worked as a sheriff's office training manager and as a patrol supervisor.
"Financial responsibility, community relations and the way we manage our agency are all going to be my top priorities as sheriff," Trenary said.
Trenary was not present for the appointment because he was on a family vacation in Hawaii that he'd scheduled last fall. His official swearing in is expected next week, after his return.
Detective Sgt. James Upton, 53, of Monroe, also sought the job. He supervises detectives who investigate property crimes based out of the sheriff's office South Precinct. Upton joined the sheriff's office in 2003.
The County Council interviewed both contenders last week, but opted to wait until Monday to make a decision. County Councilman Dave Somers said both contenders appeared well qualified to the job.
"We have two really outstanding candidates," Somers said. "Both candidates presented themselves really well."
The sheriff is responsible for law enforcement in unincorporated Snohomish County, and provides that service under contract in several communities, including in Snohomish, Stanwood and Sultan. The sheriff's office also runs the county jail. Combined, those operations include a staff of about 700 and an annual budget upwards of $100 million.
"We've got to focus on ensuring that when people call 911, we can respond in an appropriate and professional manner," Trenary said.
The sheriff's post is nonpartisan.
The immediate concerns Trenary wants to address include the jail, where at least seven inmates have died since 2010. The federal government earlier this month agreed to conduct a review of jail operations and medical services.
"Corrections has to be a priority for us and inmate safety has to be a priority," Trenary said. "Employee safety also has to be important."
Another top goal for the new sheriff is keeping full staffing levels on patrol and in the jail.
"Like everybody, we've allowed our positions to go unfilled so we could meet our budget requirements," he said. "Now that the economy is getting better, people are leaving us, they're retiring or getting other jobs."
The sheriff appointment followed a political domino effect created by Aaron Reardon's resignation as county executive at the end of May. Reardon's departure followed a series of scandals, most recently involving him and two members of his staff.
John Lovick, who had been sheriff, was appointed by the County Council on June 3 to replace Reardon. Lovick, a retired state trooper and former state lawmaker, had been in the second year of his second term.
Voters will cast ballots in a 2014 special election to determine who serves out the remaining year left on the sheriff's term. A regular election for the four-year term is scheduled in 2015.
Both Upton and Trenary said they plan to run in those elections.
Noah Haglund: 425-339-3465, email@example.com.
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