On Sept. 7, crews were conducting regular maintenance on the 65-foot tall tower when they noticed soft spots in the three support logs.
The tower is inspected daily, but soft spots were able to develop without earlier detection because of fungus that grew inside the wood, officials said.
The tower was immediately closed and an analysis by wood and engineering experts determined the structure’s support logs need to be replaced before it can be reopened to the public.
On Friday, the MetroParks board of commissioners authorized the organization to solicit bids for a firm to repair the tower.
The tower, designed by Dayton architectural firm Earl Reeder Associates, was constructed with wood from a Douglas fir. It features a spiraling wooden staircase and an observation deck providing panoramic views.
The landscape and gardens surrounding the soon-to-be repaired tower were designed by Belgian landscape architect Francois Goffinet.
The Cox Arboretum MetroPark is at 6733 Springboro Pike.
MetroParks covered about half the cost of the tower. About 400 donors also contributed to the project.
“We’ll work very hard to get this solved as quickly as possible and get it back in the public’s service,” she said.