Didn't get to this yesterday, but Eye on Williamson was on it: The State Auditor released a report on TxDOT's claimed funding gap. To sum it up, the way they calculate their much-trumpeted $86 billion shortfall is baloney.
The accuracy of the estimated costs for metropolitan and urban regions cannot be determined because of the lack of supporting documentation.
The methodology the Department used to calculate the amount of the funding gap provides a general assessment of the statewide need for additional mobility funding; however, it may not be reliable for making policy or funding decisions. To calculate the funding gap, the Department collaborated with the eight largest metropolitan planning organizations to obtain cost estimates, and it used those estimates to determine the funding gap for metropolitan regions. The Department provided some guidance to the metropolitan planning organizations. The data the Department used were cost estimates that were self-reported by the metropolitan planning organizations. The cost for urban regions was estimated by the Department based on broad and generalized assumptions. For the estimated costs in rural regions, the Department relied on cost estimates for the Texas Trunk System (a project developed in 1990 to connect the rural regions of the state with a statewide system).
The Department and metropolitan planning organizations also asserted that the main benefit from funding gap estimates was the increased communication and shared responsibility between the entities to address mobility and funding challenges. The Department stated that it plans to update the funding gap estimate every two years and make improvements to the reporting methodology.
That $86 billion figure has been cited repeatedly by Texas Department of Transportation officials and some legislators as a major reason for the state's increasing need for new toll roads. The number is a compilation of estimates from local transportation planning agencies around the state that were produced at the behest of the Transportation Department.
The report said those estimates include mathematical errors and that another $36.9 billion needed for projects in metropolitan and urban regions was "undocumented" and that $8.6 billion of the overall total should not have been included because of mathematical errors and other flaws in the estimates.