Developing Transportation ROI Metrics: Easier Said than Done

Prickly details

Prickly details

Calling for a “consumer-based transportation model,” House Speaker William J. Howell intends to submit a bill in the upcoming session of the General Assembly to base project funding decisions upon “specific, quantifiable and measurable metrics.” The hope is that money will start flowing to projects not on the basis of politics and ideology but on the amount of congestion relief, improved safety and economic development they offer.

I have been touting such an approach for years. I even took a stab at using congestion and safety measures to gauge the benefits of the Charlottesville Bypass, guesstimating that the project would yield a sup-par 3.3% Return on Investment.  Since then, Virginia’s Office of Intermodal Planning and Investment has started developing its own methodology for linking transportation goals to investment priorities for the purposes of long-range planning.

The task doesn’t sound so difficult in the abstract. But it can get prickly when you get into the briars and thorns. The federal government has launched a similar initiative as an outgrowth of its 2012 MAP-21 legislation. That law set into motion the development of performance-based criteria for surface transportation investments, including road, rail, bike and pedestrian travel.

As Tanya Snyder reports for the D.C. Streets Blog, once you start digging into the metrics, they get complicated real fast. The Department of Transportation opened up a web-based dialogue and got an earful — much of it very constructive, but all of it adding to the complexity of the task.

For example: How do you measure highway congestion? By tracking the average speed of travel on roads and highways? By the number of hours of congestion? It doesn’t sound too daunting. But the Texas Transportation Institute recently introduced the “planning time index,” which purports to measure the extra amount of time people build into their trips to avert the risk of delays. That measure recognizes that congestion varies widely, depending upon weather, accidents or special events, creating uncertainty. Should transportation metrics incorporate planning time?

Another example: Roads and highways exist to accommodate the high-speed movement of cars and trucks over comparatively long distances. But the function of streets, in the taxonomy of transportation, is to accommodate cars, buses, bikes and pedestrians in order to provide local access. The thrust of the “complete streets” movement is to balance the needs of all transportation modes. Metrics that focus exclusively on the movement of cars would short-change other transportation modes. Sounds great — but how do you measure bicycle and pedestrian traffic? And how do you weigh the utility of free-flowing conditions for, says, cars vs. bicycles?

The potential exists for transportation metrics to become a tangled mess in which road, transit, bike and pedestrian advocates seek to shape the metrics to favor their preferred transportation mode. Sigh. I guess that’s inevitable in a democracy. The key to making this work in Virginia is to develop an open, transparent process and give it enough time for thoughtful debate. As he drafts his legislation, Speaker Howell would be well advised to pay special attention to the process of how the metrics are determined so all interested parties get to participate.

— JAB