At the same peer-to-peer exchange in Iowa that we have been discussing for the past month or so a good friend told me he believes state DOTs should just buy or rent the hardware to gather work zone data and integrate their outputs with that state’s existing TMC system. Caltrans has done the same thing in District 7 – Los Angeles.
This seems to make good sense on the face of it. Why, they ask, should you pay for the “same” software twice? You already have good system operations software that measures traffic flow and sends that information to 511, websites, variable message signs, and more. They also argue that TMC operators don’t want to (or won’t) toggle back and forth between two software packages.
But when you look into it further you find this path is filled with problems.
First, you learn the software is not the same at all. Systems operations software measures and acts upon traffic flow at the system level. It looks at it from a regional or state perspective. It does not “zoom in” to the project level to find and react to queuing or slowing occurring in a specific work zone.
This goes back to my earlier post regarding the difficulty of explaining the value of detailed work zone data to systems operations folks. We know it is important to know where the slowing occurs. Then we can make adjustments in our traffic control to maximize throughput and safety.
The other important aspect of this is the need to learn about problems immediately. By doing so we can react quickly to eliminate or at least minimize the problem causing the slowing. This increases throughput, greatly reduces secondary collisions, and improves safety.
Another problem is the equipment itself. Someone must maintain it. And new improved equipment is introduced every month. Software is evolving in our industry but hardware will continue to make quantum leaps in design, functionality, expense, communications, and areas we have not even considered yet. So it just doesn’t make sense to tie up precious dollars in equipment that may just sit in the DOT yard.
The third important problem with this procurement method is that work zone ITS elements move. That is by design. Someone must watch that to be sure the system is working properly. Also, most system operations software does not take this into account. They don’t normally offer robust GPS device tracking. So anytime a sensor is moved, for example, someone must manually update the gui maps, and system location information.
I understand where this strategy is coming from. The DOT wants to use more work zone ITS on their projects but they haven’t found a satisfactory way of getting both competitive bidding AND a system that performs to the specification. I think we will learn how to do that in time. Meanwhile it is far better to jump in and try things. Learn what your needs truly are and then you can put a better specification together next time. And make this the responsibility of a contractor who will focus on the system for one particular work zone to get the best possible performance at that location.