Times Record Estimated costs of constructing the I-49 bridge and a possible bridge to reroute traffic away from downtown Fort Smith aren't cheap, but one state official says there's a lot to be considered in the projections. Halff Associates estimated the cost of constructing a bridge in eastern Oklahoma to reroute trucks off of Garrison Avenue would be $225 million. It's less than the estimated cost of the I-49 bridge to connect Chaffee Crossing to Alma, which Arkansas Department of Transportation District 4 Engineer Chad Adams estimated would cost between $300 million to $400 million. These estimates come as ArDOT has launched an 18-month traffic study that will assess how to best alleviate truck traffic in downtown Fort Smith, including the possibility of a bridge. It also comes on the heels of the passage of Issue 1, which Arkansas Highway Commissioner Keith Gibson said will secure $270 million in the next 10 years toward I-49 through the extension of the state's 0.5% state sales tax.