Drivers on southbound MoPac can expect to see construction and lane closures happening this weekend between Parmer Lane and Duval Road in North Austin. The Central Texas Regional Mobility Authority will be closing the center and left main lanes as well as the southbound toll lane starting at 7 p.m. tonight, June 22. The closures are necessary to allow workers to remove asphalt and lay down new concrete in the left main lane on the bridge over Waters Park Drive and the Capital Metro commuter rail line, said Steve Pustelnyk, director of community relations for the Mobility Authority. He said the concrete bridge deck may have been damaged when workers removed old asphalt last year. The exit to Duval Road will remain open so that drivers may avoid construction and any delays. At 5 a.m. Saturday, the southbound express toll lane will reopen while the concrete in the left main lane cures. From 5 a.m. Saturday to 9 p.m. Sunday, drivers can use the express lane between Parmer and RM 2222 at no cost while the left and center main lanes remain closed. On Sunday at 9 p.m., the express lane will close again so workers can lay down asphalt. All travel lanes will reopen by 5 a.m. Monday. Pustelnyk said other minor asphalt repairs also will occur this weekend throughout the MoPac corridor. For updates, visit www.mopacexpress.com or follow the Mobility Authority on Twitter at @ImproveMoPac.