CHICAGO (CBS) — Mayor Lori Lightfoot is losing a member of her cabinet, but gaining another, as the city announced the retirement of Library Commissioner Andrea Telli, and the appointment of Annastasia Walker as executive director of the new Office of Public Safety Administration (OPSA).

Telli, who has worked in various jobs in city government for 30 years, has been commissioner of the Chicago Public Library system since last June, when she replaced Brian Bannon as Lightfoot took office.

During her year in office, Telli oversaw the decision to eliminate all late fees – becoming the largest public library system in the U.S. to go fine-free – and to expand Sunday hours.

“The library has always had a special place in my heart. It’s where I gained the ability to dream, imagine, and tell stories. It’s how I met my lovely wife, Amy. And it’s where I met my good friend, Andrea. Thanks to Andrea, Chicago’s libraries will continue to have a central and trusted role within our communities, as we begin a national search for her successor. I want to extend my warm congratulations to Andrea for her well-earned retirement and wish her and her family nothing but the best as they begin this exciting, new chapter of their lives,” Lightfoot said in a statement.

Meantime, the mayor’s office announced Walker will be the first executive director of the new Office of Public Safety Administration. Currently the chief administrative officer at the Chicago Fire Department, Walker will be tasked with overseeing the city’s effort to merge the administrative functions of the CFD, Chicago Police Department, and Office of Emergency Management and Communications.

Originally scheduled to launch in May, the launch of OPSA has been delayed by the COVID-19 pandemic, and the new agency will begin operating by the fall. The city has said merging the administrative offices of CPD, CFD, and OEMC under one new agency will allow officials to move 151 police officers and 11 firefighters out of headquarters and back into the neighborhoods. The 280 civilian staff in those agencies will work for OPSA out of Public Safety Headquarters in Bronzeville.

“I am honored to serve as the Executive Director for this new office so that we can build a safer and stronger Chicago by ensuring the efficiency of our public safety operations,” Walker said in a statement. “I look forward to working alongside our police, fire and emergency response leaders on strategies that will reduce costs, streamline operations and increase efficiencies so that Chicago’s first responders can focus on protecting and serving Chicago’s communities.”

According to the mayor’s office, each of the city’s public safety agencies previously had their own operational and data-tracking systems, which were designed only to meet their own individual needs, often leading to inefficient use of resources and increased costs for services that affect all of the city’s first responders.

“Walker’s expertise and leadership will ensure that through the new Office of Public Safety Administration, this City is maximizing police, fire and emergency management resources in a coordinated and collective effort that will make a safer Chicago for all residents,” Lightfoot said in a statement.