Cornell Robertson said he is "excited about the opportunity" to succeed his mentor, Dean Ringle, who retired after serving 17 years as Franklin County's elected engineer.
Robertson, a 47-year-old Hilliard resident, was named acting county engineer June 15.
The Franklin County commissioners appointed Robertson, a Republican, to succeed Ringle, who also is a Republican and on July 1 will begin serving as executive director of the County Engineers Association of Ohio.
The Republican Party Central Committee on June 20 also was expected to name Robertson as the party's nominee for the next election.
He must be elected in 2018 to remain in office; voters will elect an engineer for a full four-year term in 2020.
The appointment occurred 25 years to the day that he began his tenure with the Franklin County Engineer's Office, Robertson said.
"It just worked out like that; it was not planned that way," said Robertson, who began working at the engineer's office June 15, 1992. "I'm excited about the opportunity to continue Dean's great work. He has been a mentor to me."
Since 2013, Robertson has been chief deputy engineer and second in command at the engineer's office.
Ringle recommended Robertson as his successor.
He described Robertson as "well-rounded in all areas," crediting his work on such projects as the Lane Avenue bridge on the Ohio State University campus and the intersection of Alum Creek Drive and Groveport Road.
"I'm more than comfortable with handing (leadership) of the office over to him," Ringle said.
The appointment also will have an effect on a Hilliard office: Robertson said he will resign from his post as a member of the Hilliard Planning and Zoning Commission, reducing its number of members from six to five.
Robertson said he inquired with Franklin County Prosecutor Ron O'Brien but was advised that remaining on the commission would be a conflict of interest.
The commission is a seven-member body but has been operating with six for the past several years.