AEP (NYSE:AEP) announced today that Texas regulators have unanimously approved the application of Electric Transmission Texas, an AEP joint venture with MidAmerican Energy, to build a $318 million, 156-mile long 345-kB transmission line.

In a regulatory approval sweep, the Public Utility Commission of Texas' stamp of approval also included settlements with almost 100 landowners, as well as the Texas Parks and Wildlife department. The line will run between Laredo and Edinburg, and will include two new substations.

"Approval of the CCN is a significant step to ensuring continued transmission reliability in the Rio Grande Valley and Laredo areas," said Electric Transmission Texas President Calvin Crowder in a statement today.

AEP's transmission network currently includes 40,000 miles of lines, including 2,100 miles of higher-voltage 765-kV lines, "more than all other U.S. transmission systems combined."

According to the release, construction should begin in 2014, and is expected to be completed by 2016.