Interstate 37 begins at Waco Street before heading west through the city. West from US 181, the freeway heads meets SH 286 and SH 358 in quick succession. Paralleling the course of the Nueces River, IH 37 bends northwestward to meet IH 69 & U.S. 77 in Calallen before turning northward toward San Antonio. IH 37 is six lanes wide through Corpus Christi, with increased traffic volume as development moves west of the city and out toward small towns such as Orange Grove. The first section of IH 37, the interchange with US 181, opened in November 1959.
The Harbor Bridge Project, replacement of the existing U.S. 181 Harbor Bridge, includes reconstructing portions of both IH 37 and the Crosstown Expressway (SH 286). Work along IH 37 replaces the freeway extending east from SH 286 with an at-grade boulevard, as the new alignment for US 181 ties into a rebuilt interchange with SH 286. Ground breaking for the $802.9 million project took place on August 8, 2016, with construction effecting IH 37 forecast for completion by spring 2020.