Fulton County's chief operating officer, who was the architect behind a transportation tax to improve roads and sidewalks in the county, will leave in June.

Todd Long, who was the deputy commissioner of the Georgia Department of Transportation before he came to Fulton County in 2015, will return to the transportation industry, a statement from the county said.

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That expert said he believes the office is turning itself around

In his role, Long handled the transition of services from Fulton County to the new city of South Fulton. He also worked on a plan to expand transit in Fulton County and the rest of metro Atlanta.

“He’s had an enormously positive impact as a leader,” said Dick Anderson, the Fulton County manager. “He’s really going to be missed.”

Long worked with Fulton's cities and the state legislature to push the transportation funding taxes that passed in 2016 in Atlanta and the rest of Fulton County. He was also instrumental in negotiating the transit legislation that was approved this year, and could lead to votes on transit expansion in Fulton and other counties.

Anderson said his impact on Fulton County transportation improvements was easily in the hundreds of millions of dollars.

“He could’ve done nothing other than that, and really earned his pay,” Anderson said. “I truly believe it would not have been possible without him.”

The county will rely on an outside firm that conducted its transit study to move the process forward, Anderson said, and he does not expect a vote to happen this year.

The county will begin a search for Long’s successor.