PORTLAND — Outgoing City Manager Joe Gray told several hundred business people this morning that Portland has evolved over the last 40 years from a relatively isolated town with a limited business community to a diverse, connected and culturally-rich city.

His remarks were made at the Portland Regional Chamber’s monthly Eggs & Issues business breakfast.

Gray attributed much of the city’s progress to effective urban planning. Unlike other cities in the Northeast that underwent urban renewal in the 1960s, Portland has maintained much of its original character.

“We didn’t tear down the architectural fabric of the town,” he said.

Gray also discussed Portland’s future and upcoming challenges.

He called “problematic” the city’s reliance on property taxes to fund local government, programs and facilities, such as the Barron Center, which provides long-term care to the elderly.

“We run a number of operations for a city our size,” he said in an interview. “It adds to the cost of local government. It’s important, but it costs money.”

Gray said at the breakfast that the local economy continues to change and is becoming more reliant on tourism and life science and biotechnology firms, and less tied to manufacturing.

And he stressed that the next city manager must form a partnership and have “good chemistry” with the city’s incoming mayor, a post that Portland voters approved last fall.