In 1989, California became the second state in the U.S. to authorize the use of public-private partnerships (P3s) to deliver transportation improvements when the legislature enacted Assembly Bill (AB) 680. This bill authorized the California Department of Transportation (Caltrans) to enter into agreements with private entities that would construct up to four toll projects around the state at their own expense and without state funds to supplement existing state-owned transportation facilities. The legislation authorized Caltrans to lease those facilities to the private entities for up to 35 years, and allowed private concessionaires to identify specific projects where a private facility would perform favorably.
When AB 680 was passed, the SBX-known at the time as SR 125-had been an approved component of California's Long Range State Transportation Plan for 20 years. The road also reinforced the vision of the 1981 Otay Mesa Community Plan to develop new residential communities in eastern Otay Mesa, encourage employment opportunities, and also coordinate the development of the Otay Mesa border crossing, which at the time was only served by local arterial streets. Although the SBX was recognized as an integral element of the region's future transportation network, it had never gained state or local funding, as the surrounding area was only beginning to see rapid growth and development.