Transportation Asset Management Case Studies - Highway Economic Requirements System-State

The New Mexico Experience

3. How did New Mexico Get There?

Even with all of the refinements to the pilot software, NMDOT still found HERS-ST lacking in terms of report options, an an issue that has been addressed with subsequent program updates. Undaunted, NMDOT's planners began manipulating HERS-ST data and generating their own customized reports.

Creating these documents required in-depth study of the nuances of HERS-ST and creation of multiple layers of formulas in various Excel spreadsheets. NMDOT's Transportation Fact Sheet, for example, takes the improvement costs calculated by HERS-ST by funding period, by rural and urban designation, and by functional class and multiplies the improvement costs times the benefit-cost ratio generated by the program to compute total user benefits. NMDOT's goal in preparing this report was to present the basic information on engineering needs and projects with a benefit-cost ratio of 1.0 or greater in a concise, straightforward manner.

And NMDOT's outside-the-box thinking didn't stop there. When the State was looking at expanding a 235-mile stretch of US 54 to support two lanes of traffic in each direction, it employed HERS-ST to consider a four-lane option and analyze factors such as vehicle miles traveled (VMT), vehicle hours traveled (VHT), delay times and so forth. Utilizing Regional Economic Models, Inc. (REMI) Policy Insight/TranSight methodology in conjunction with the HERS-ST data, the State was able to determine that the benefits of the proposed expansion would be to commercial freight carriers and travelers to Texas rather than to New Mexico residents!

Finally, NMDOT showed its commitment to HERS-ST by supporting the planning division's involvement with the HERS-ST developers' group. That group meets two to three times a year to evaluate comments and work on software changes and priorities.

Table 1: One of NMDOT's customized HERS-ST reports. New Mexico Department of Transportation Transportation Fact Sheet Twenty-Year Highway Needs and User Benefits of Improvements: Benefit/Cost Basis in $1,000s