A vendor just told me a story. He recently spoke at a meeting with state DOTs and afterward one of them stopped him to say, “You are right. These systems will save us money and they will save lives. We should have them on every project.” He went on to add, “I don’t care about data. I just want the system to work.” This vendor told the man he was wrong. His explained that unless you know the data is coming through on a consistent basis and that it is accurate, it is not a safety system. It doesn’t just need to gather data and act on it. It must do so correctly.
He used queue warning systems as an example. The system must change message signs upstream at the right time and with the correct message or the system is not improving safety or efficiency. This is yet another reason why agencies can’t just include a work zone ITS system in the traffic management plan and then call it done. They have to perform their due diligence. And that means wading into the data.
This doesn’t need to be a big deal. First check to see that data is flowing in on a regular and timely basis. If there are large gaps, they could result in warnings that arrive too late to do any good. Then look at the times when it showed slow traffic and find ways to confirm the average speeds shown at that point in time. Check the logs to be sure the message signs changed when they were meant to do so. After you have done this two or three times, you will find its not difficult to do. And you will be far more confident that the system is working as designed and that you are getting what you paid for.