Santa Rosa Mayor Scott Bartley further shook up an already wide-open City Council race Wednesday by announcing he will not run for re-election this fall.

Bartley, 57, said he will not seek a second council term because he needs to focus on running his Larkfield-based architecture firm, Hall & Bartley.

“The bottom line is the economy is turning and my business needs me,” Bartley said.

The firm has received some significant new clients recently and it became clear that a re-election campaign would make it harder for him to serve those clients effectively, he said.

“My profession is cyclical, and we’re in an upswing right now,” Bartley said. “The civic duty is fun. I enjoy it, but it’s not my career. Architecture is my career.”

His decision means none of the three incumbents with seats up for grabs on Nov. 4 will try to retain them. Vice Mayor Robin Swinth — appointed last year to fill Susan Gorin’s vacant seat — and Councilman Jake Ours previously announced they would not run again.

The development means the field of announced candidates drops to six: Planning Commissioner Curtis Byrd; former Press Democrat columnist Chris Coursey; Planning Commissioner Ashle Crocker; former Councilman Lee Pierce; former Councilman John Sawyer; and former Police Chief Tom Schwedhelm.

Incumbents have until 5 p.m. Friday to file paperwork to qualify for the ballot. The filing deadline will now be extended until Wednesday, Aug. 13, for non-incumbents.

Though he had previously said he was running, the fact that Bartley had yet to begin the filing process so close to the deadline raised suspicions among council watchers that he might not. His noncommittal response to the question last week cast further doubt on his future plans.

Bartley said he wanted to wait until after the council hired a new city manager to announce his decision. The council on Tuesday appointed Sean McGlynn, a deputy city manager from El Paso, Texas, as the new city manager. He begins work Sept. 13.

Bartley’s tenure as mayor has seen the stabilization of city finances and an improvement in the city’s business climate. But the past year also has been a tumultuous one marred by council infighting, labor unrest, the investigation and censure of a colleague, and criticism of city leaders in the wake of the Andy Lopez shooting.

Bartley was losing two of his staunchest allies, Swinth and Ours, and had seen some erosion of support from groups that backed him in his previous election.

Some members of the business community were none too pleased by Bartley’s support of a sharp increase in permit and development fees earlier this year.

“There’s no way that these other things haven’t had some impact,” said David McCuan, political science professor at Sonoma State University.

Bartley’s opponents inevitably would have taken aim at some of the issues that arose during his term as mayor. While he would likely have survived his re-election bid, his campaign would have been forced into the uncomfortable position of playing defense over his record instead of focusing on a more forward-looking message, McCuan said.

The notion that these other issues played a role in his decision “holds no water whatsoever,” Bartley said.

The council infighting has been “irritating and frustrating,” he’ll miss his departing colleagues, and the business community will get over the fee increases, especially when they see an upcoming and more sharp drop in water and sewer hook-up fees, Bartley said. He said he’s proud of his record and wouldn’t have had a difficult time defending it to voters. The decision is strictly a business one, he said.

“I want to be working at 70 because I want to work at 70, not because I have to work at 70,” he said.

Bartley’s departure changes the dynamics of the race from one in which the question is no longer which candidate will pick up the third seat behind Bartley and Schwedhelm, who is widely viewed as a strong candidate, but which two new candidates will join Schwedhelm and what it means for the balance of power in the city, McCuan said.

You can reach Staff Writer Kevin McCallum at 521-5207 or kevin.mccallum@ pressdemocrat.com. On Twitter @citybeater.