Renewing the National Commitment to the Interstate Highway System: A Foundation for the Future

We are looking forward to the American Traffic Safety Services Association (ATSSA) Midyear Meetings. https://www.atssa.com/Events/Midyear-Meeting  They will be held next week (August 21 to 23) in San Diego. There will be many topics of interest including the joint working group with the Automotive Safety Council discussing automated vehicles and how their systems will communicate with work zones and a new Traffic Signals working group meeting to form a new division in ATSSA.

Not on the agenda, but sure to be another topic of conversation is a document recently published by the Transportation Research Board (TRB) titled, “Renewing the National Commitment to the Interstate Highway System: A Foundation for the Future (2019).” This report was requested by Congress to facilitate their discussions on the future of highway construction, maintenance and most importantly, funding.

Download a copy of the report HERE.

The report begins by looking at the history of the national highway system, then examines the needs for current and future maintenance and expansion and the funding problems of the trust fund. Finally, it offers a “Blueprint for Action” including these 10 recommendations:

  1. Congress should require a new program to rebuild and revitalize our existing highway system.
  2. They should work with states to “right size” the highway system, adding capacity where needed to meet developing demand.
  3. FHWA should work with states to assess the structural integrity of existing pavements and use that to decide when full reconstruction is more cost-effective than repaving.
  4. These improvements should be paid for by immediately raising the federal fuel tax to cover the federal share of the investment in renewal and modernization.
  5. Congress should allow states and local agencies to toll existing roadways as a way of helping them pay their share of these improvements.
  6. To avoid future funding shortfalls due to changes in technology, Congress should prepare to change from a per gallon fuel charge to a miles-driven or other user-based system.
  7. A new database of pavement conditions should be developed and combined with new modeling software to help make better decisions regarding the roads that should be improved.
  8. Begin preparing for connected and automated vehicles by learning what they will need in terms of roadway safety infrastructure including pavement markings signs, and temporary traffic control devices.
  9. With the goal of a more resilient highway system, assess the potential threats to our roadways from climate change and extreme weather and determine where improvements to our roads should be made.
  10. Recommend ways of reducing greenhouse gas emissions.

As Congress works once again on a new highway bill, this document is sure to be a part of the discussion. Most of these 10 recommendations fit nicely with ATSSA’s efforts to improve roadway safety. Familiarize yourself with these recommendations and include them in your next conversation with your elected representatives!

Innovate.ATSSA.com

As most readers will know, I’ve been involved in work zone ITS for nearly 20 years now. So I assume most people are aware of the technology and aware of the availability of studies, best practices, specifications, and more. But one should never assume, especially in a discipline where new practitioners are arriving every day.

This was hammered home to me in a phone conversation yesterday. A fellow contractor complained about a state that just let a project with a work zone ITS spec that no one can meet. Another person on the call told a similar story about an engineering firm.

This is compounded by the fact that those not in our industry don’t know where to begin their research. For that reason the American Traffic Safety Services Association (ATSSA) has created the “go-to” website for work zone ITS. You will find it within their Innovate.ATSSA.com website at: http://innovate.atssa.com/work-zone-its.html

This website was just introduced to members in February. It is still new so we are adding resources every day. But because it is new, you can be sure that everything there is current and the best information available.

On the ATSSA website you can learn about new technology, you can search for projects by state, and you can view upcoming industry events where you’ll be able to learn more. There is a blog area where you can read this and many other work zone ITS – related blogs. And most important there is a large section devoted to news and resources. Check it out today!

Variable Speed Limit Webinar

Variable speed limits systems have always, at least intuitively, promised benefits for work zones including greater throughput, reduced speed variance, and as a result, fewer crashes. We discussed these systems in a post in October 2015 after a presentation at the National Rural ITS meeting in Utah. The concept made sense and we looked forward to greater use of VSL systems.

A webinar was just offered April 4th by the US DOT Office of Assistant Secretary for Research & Technology entitled, “Variable Speed Limit Systems – Are They For Everyone?” The speakers, and there were several of them, did a great job of explaining the advantages and disadvantages of these systems. Those speakers included Jimmy Chu of FHWA, John McClellan of MnDOT, Bryan Katz of Toxcel, Jiaqi Ma of Leidos, and Vinh Dang of WsDOT.

There wasn’t a lot of new information. Instead they presented a comprehensive history of VSL systems from around the country. They looked at different uses for these systems, including work zones. In all, more than a dozen different projects from 9 different states were discussed. Some projects were relatively small, and others like those in Minneapolis and Seattle, were quite large.

But in almost every case, the results of these systems have not met expectations.  This was true for weather related systems, work zones, and congestion management applications. Reductions in speed variance and crashes were very small if not non-existent. And the reason in every case was a lack of conformance by the traveling public. There was some smoothing, but very little.

Many of the system designers anticipated this and included variable message signs alongside the VSL signs to explain why the speed reduction was justified. But drivers either misunderstood when they were supposed to slow or simply chose to continue at their current speed until they saw the problem for themselves.

Law enforcement is critical for these installations. Without enforcement, compliance will never reach levels that will result in the benefits designers expected. But law enforcement often became distrustful of the data they received, or didn’t get timely notifications at all. They also ran into serious resistance from the courts. So enforcement slowed, and compliance tanked.

There is still hope that these issues will one day be resolved. But for now, variable speed limit systems just aren’t providing the benefits we all hoped to see.  The webinar closed with a short discussion of future considerations. One thought was to combine these systems with a larger big data process (as discussed in our last post). They might look at not just weather, or work zone conditions, but also at traffic speed and volume data approaching the area, timing of major events, and more to improve drivers trust of VSLs.

Another thought was with regard to automated vehicles. Will VSL systems be more effective when the information is sent directly to each vehicle? If a pop-up display recommends slowing to 35, will they be more likely to do so? Or will they continue to ignore them as they apparently do now? Once autonomous (driverless) cars are on the road, the recommendations from these systems will be adopted automatically. But until then, compliance will remain the biggest problem for VSLs.