Woodland Park City Manager David Buttery told City Council Thursday night that he plans to retire in four months.
Mayor Neil Levy called for an executive session to discuss Buttery's decision, then said that he and the City Council will begin recruiting a new city manager immediately.
"We will draw on the expertise of our partners at the Colorado Municipal League and the Colorado Department of Local Affairs for a transparent search," Levy said.
Buttery has worked for the city for 20 years. He was hired as public works director in 1997, following a 21-year Army career.
Buttery said he had planned on retiring in 20 years, which was up in July, but he wanted to stay to see the completion of renovations to the town's Memorial Park, the building of the Woodland Aquatic Center and adoption of the 2018 budget, which he said he "knew would be a challenge."
Council adopted the budget Thursday, after it was sent back to be redone last month to address what some had called a "dangerously low" emergency fund balance.
"I want to thank this and previous councils for allowing me to serve our citizens, businesses and visitors," Buttery said in a statement. "I want to thank our dedicated staff for serving alongside me to make this the wonderful place that it is to live, work and play."
Buttery led the city through several significant improvement projects and at times has clashed with business leaders.
Buttery was dismissed as interim director of the city's Downtown Development Authority in July 2016 by the organization's board. The organization assists the city with economic development and other projects. Investigations into its finances and some alleged missing emails, which later were located, did not show any wrongdoing.
Business operators have criticized the city's permitting rules and the way the city handles contracts under Buttery's reign.
The mayor said the city has been "fortunate to have the steady direction" of Buttery.
Buttery's contract requires he give a 120-day notice before leaving the position.