The Texas Department of Transportation is in the midst of a $42.6 million project to improve I-35 in the Oltorf Street area with work expected to be complete by the end of 2019. As part of that project, construction crews will be replacing overhead sign bridges on I-35 overnight April 9, leading to some closures and detours in the south Central Austin area. The I-35 southbound main lanes and ramps will begin to close at 10 p.m. with full main lane closure scheduled at 11:45 p.m. In addition, Woodland Avenue and Oltorf will close at the intersection of I-35. Highway southbound drivers will detour to the frontage road at the Woodland/Oltorf exit and will re-enter I-35 at the entrance ramp south of Oltorf. Drivers crossing I-35 should use Woodward Street or Riverside Drive while Woodland and Oltorf are closed.