51st Street project location 51st Street project location[/caption] The southbound to northbound I-35 turnaround bridge in Austin will close at 51st Street as part of Texas Department of Transportation work on Mobility35 improvement efforts. Road signs are in place to alert drivers of the closure, which is scheduled for Sunday, Jan. 8 starting at 8 p.m. Drivers should allow extra time to travel through the area, as those heading southbound will have to use the signalized intersection at 51st Street to go north on I-35, according to a TxDOT news release issued Tuesday. Work is underway to reconstruct the bridge, which will be realigned to work with the new roundabout configuration at 51st Street, according to TxDOT. The reconstructed bridge is expected to be opened to traffic in early April. The $16.5 million project is expected to be complete in early 2019. Nearly 215,000 vehicles travel daily on that segment of I-35, according to TxDOT.