Construction on the project is set to begin within months, but funding for the portion that includes the trestle over Trail Creek hinges on voters extending a 1 percent sales tax for capital projects.
Voters approved $2.5 million in sales taxes for the project in 2004; that money, along with a federal grant, will pay for a trailhead near downtown, land acquisition and a stretch of the trail east of the trestle.
"The trestle is not an issue right now because there's no money," Athens-Clarke Natural Resources Administrator Mike Wharton said.
A tax measure on the ballot in November includes an additional $7.7 million to convert the former Georgia Railroad bridge to a biking and hiking trail. That funding would complete the paved path to downtown, as well as all or part of another portion heading east to Winterville, Wharton said.
The trestle was on the cover of the early R.E.M. album "Murmur," and is commonly known as the Murmur Trestle.
Athens-Clarke County bought the trestle for $25,000 in 2001 after railroad company CSX Transportation tore down part of it to sell for scrap, prompting outrage from R.E.M. fans.
A preliminary engineering study in 2009 found that the trestle may be past the point of preservation. Some of the wood was also treated with creosote, a carcinogen.
The county's rails-to-trails committee and the Athens-Clarke Commission will eventually have to decide whether to shore up the trestle or build a new structure.
When the first 1.3-mile phase of the trail is done in about two years, it will start at a planned Athens Transit park-and-ride lot near Lexington Road and the Athens Perimeter and tie into an area near the intersection of Oconee and Oak streets, allowing commuters to walk or bike downtown or to the University of Georgia campus.