On Tuesday, September 15, 2026, City Council appointed Finance Director Mark Sullivan as interim City Manager, following the resignation of current City Manager Katie Ambrose, effective November 28.

Sullivan will serve as interim City Manager for 90 days while City Council promotes a nationwide search for a permanent candidate.

“Mark Sullivan is a capable leader who will excel in this new role,” said Mayor Chuck Grassie. “We thank Katie for her service to the City of Rochester and we wish her well in her future endeavors.”

For the past 3 years, Sullivan has served as the Director of Finance for the City of Rochester. He started with the City in 2007 as a Senior Accountant, and was promoted to Deputy Finance Director in 2018.

As interim City Manager, he plans to support the city’s growth and services, employee retention, public engagement, and fiscal strength.

Additionally, Sullivan is looking forward to fostering positive relationships with Mayor Grassie, City Council, and staff as he steps into the role.