Weak transportation data stifles analysis

By Bill Holloway

The Dallas News reports that the Texas Department of Transportation is upset with a recent report by Smart Growth America and Taxpayers for Common Sense. TxDOT claims that the report overestimates the amount being spent on expansion relative to maintenance. According to Repair Priorities 2014, states spent a combined total of $20.4 billion each year between 2009 and 2011 on building and expanding roads and just $16.5 billion on the repair and preservation of existing roads. During the same period it claims TxDOT spent more than four times as much on expansion as on preservation and repair; only six states spent less on preservation relative to capacity expansion.

However, TxDOT claims that it spends significantly more on preservation activities than it does on expansion. The disagreement is rooted in the way highway statistics are collected and presented. In particular, TxDOT’s practice of adding capacity when it reconstructs roadways makes it difficult to determine how much funding is going to reconstruction versus expansion. This table from FHWA’s Highway Statistics Series, which was used to calculate the figures presented in the report, exemplifies the way the data make it difficult to answer some key policy questions. While the table provides relatively detailed information on capital expenditures, it is impossible to determine the portion of these expenditures going toward system expansion. The category of reconstruction is divided into “Added Capacity” and “No Added Capacity.” Among reconstruction projects that added capacity it is impossible to determine how much funding went toward the capacity expansion and how much went toward reconstructing the existing roadway.

As noted in a previous SSTI article, Statewide Transportation Improvement Programs are often similarly obscure about how funding for a given project is allocated. This makes it extremely difficult to evaluate states’ performance or compare states to one another. For example, Tri-State Transportation Campaign’s Tracking State Transportation Dollars project, which uses STIP data to compare state transportation priorities, is hamstrung by the fact that STIPs do not break out the funding for the bike/pedestrian portions of larger projects.

Improving the way transportation data is collected and presented would allow for more meaningful analysis and help to reduce disagreements about basic facts—such as that documented in the Dallas News article—and clear a path for more substantive policy discussions.

Bill Holloway is a Transportation Policy Analyst at SSTI.