While most of area bridge work is still years away, the Georgia Department of Transportation is making some headway on a few key projects that could start within the next year.One of the biggest projects on the horizon is the replacement of Ga. 284/Clarks Bridge Road bridge over Lake Lanier, near Clarks Bridge Park and the Olympic rowing and canoe and kayak venue.The DOT is “working to get environmental studies updated” for the Federal Highway Administration and with the U.S. Army Corps of Engineers on permitting, said Teri Pope, a spokeswoman based in the DOT’s District 1, which includes Hall County.The project has a tentative December bid letting, with work possibly starting in the spring, Pope has said.Right-of-way acquisition is finished.“The lake is a very sensitive area and we are being extremely diligent and careful to ensure we protect (it) before, during and after this project,” she said.The work features a 63-foot pedestrian tunnel connecting Clarks Bridge Park and the boathouse shared by the Lake Lanier Rowing Club and Lanier Canoe and Kayak Club to the venue and boat ramps.Overall, the new bridge will be 952 feet long, nearly 50 feet wide and have five columns in Lake Lanier. Bike lanes and sidewalks will run along Ga. 284/Clarks Bridge Road for 2,781 feet, officials have said.The current bridge, built in 1958, is 834 feet long and nearly 24 feet wide. Its 2010 average daily traffic count was 6,130 vehicles, Pope said.Plans call for workers to “build the new bridge parallel to the existing structure, then shift traffic to the new bridge and demolish the old bridge,” she said.The project is estimated to cost $8.6 million.Elsewhere, maintenance work on the Ga. 53/Jasper Highway bridge over the Amicalola Creek in Dawson County is wrapping up and the bridge could fully reopen this week, Pope said.“Scheduling the last of the subcontractors has been difficult,” she added.