SONOMA – Bank of Marin opened the doors of a new 3,000-square-foot branch in downtown Sonoma today, the third branch opened this year and the fifth in Sonoma County.

The branch will employ five people on-site, with one additional employee dividing their time between Sonoma and Petaluma, said Bank of Marin CEO Russ Columbo.

 “We’re really thrilled to have it opening-we have a number of customers already in Sonoma,” Mr. Colombo said.

Sonoma-based Jenkins Construction completed work on the branch.

“It’s perfect -- the building looks great, it’s right in the middle of town,” he said.

Bank of Marin has added approximately 50 employees this year, growing to a staff of nearly 250, Mr. Colombo said. The bank opened a branch in Santa Rosa in 2011 and acquired the insolvent Charter Oak Bank in Napa in February.

Westamerica Bank foreclosed on the original owner of the Sonoma building earlier this year, after Bank of Marin had already signed a lease and was preparing the space on the front part of the structure. The CEO said he was pleased with the new landlord and work that the owner had invested into the building.

Bank of Marin first announced their lease for the location in Dec. 2010.

The bank will hold an open house at the new location, 136 W. Napa St., from Tuesday, Oct. 11 through Friday, Oct. 14. A ribbon cutting ceremony and Sonoma Chamber of Commerce mixer will be held at the site on Oct. 13, from 5-7 p.m.

This year has been a period of rapid growth for the 21-year-old Bank of Marin Bancorp. The bank now has 17 offices across Marin, San Francisco, Napa and Sonoma counties, with assets exceeding $1.3 billion, according to an announcement.

Marck Zuehlsdorff will serve as the new location's branch manager, with Claudia Levindofske as assistant branch manager. Carol Kneis will work in business development.