In June 2006, OCTA, the Riverside County Transportation Commission (RCTC) and the Foothill Eastern Transportation Corridor Agency (TCA) joined together and formed the Riverside Orange Corridor Authority (ROCA) to develop and manage geotechnical studies regarding a proposed transportation and utility corridor linking Riverside and Orange Counties. ROCA has been formed to ensure that the needed geotechnical work is completed as quickly as possible.
The goal of building a new highway corridor between the two counties was one of three major recommendations that were advanced at the conclusion of an 18-month Major Investment Study (MIS). Additional recommendations included improvements to State Route 91, a new parallel corridor built within the State Route 91 right-of-way and better use of the existing transportation system that would include additional Metrolink and express bus service.
Many of these recommendations are already being implemented; however, the development of a new highway between Riverside and Orange Counties faces a number of challenges due to its location. Most alignments for a new corridor involve the Santa Ana Mountains, Cleveland National Forest, and an earthquake fault, which means that any facility will require significant tunneling.