As planning and schematic design continued into the early 2000s, TxDOT and its regional and local partners began to look more closely at the project's estimated cost and sources of funding. However, by 2003, only a small amount of funding from state and local sources had been secured.
TxDOT considered the option of delivering the project through a conventional approach where final design, right-of-way-acquisition, and construction would progress sequentially as available public funding permitted. It also considered an alternative approach that would capitalize on recent enhancements to Texas transportation law that permitted TxDOT to engage the private sector to finance, design, construct, operate, and maintain a toll road project. Known as a public-private partnership (P3) and referred to as a comprehensive development agreement (CDA) in Texas, this approach would allow final design, right-of-way acquisition, and construction to take place concurrently, with access to private sector financing helping to accelerate the delivery of the project.
Given the lack of sufficient funding from traditional sources and the desire to relieve congestion as quickly as possible, TxDOT and its local partners agreed that the P3 (CDA) model offered the best option for accelerating construction. This consensus was formalized through the work of the I-635 Corridor Coalition, a group representing a broad spectrum of businesses, local governments, and community groups. In 2004, the Coalition requested that the Texas Transportation Commission, the governing board of TxDOT, direct the department to pursue a P3 agreement to implement the project.