I did my college senior design on this. To put things in perspective, the city of San Jose, CA is currently doing a similar upgrade to the city's traffic signa

I did my college senior design on this. To put things in perspective, the city of San Jose, CA is currently doing a similar upgrade to the city's traffic signals and controllers at a cost of ~25 million dollars. While it is expected to save money in the long run, that's a serious chunk of change. The project (as government contract jobs tend to do) has also gone several years past its due date.