Computer Failure Causes Gridlock In MD County

Uncle Rummy writes "A central traffic control computer in Montgomery County, Maryland failed early Wednesday morning, leading to widespread gridlock across the entire county. The computer, which dates to the 1970s, is the single point of unified control for all traffic signals in the county, which comprises a number of major Washington DC-area suburban communities. When the system failed, it caused all signals to default to stand-alone operation, rather than the highly-tuned synchronization that usually serves to facilitate traffic flow during rush hours. The resulting chaos is a yet another stark reminder of how much modern civilization relies on behind-the-scenes automation to deliver and control basic services and infrastructure. The system remains down Thursday, with no ETA in sight."

Comments

MontCo $$

[headhot]

For those who aren't familiar with Montgomery County, MD. It is one of, if not the richest counties in the nation. I find it amazing that even in a county like this, the public infrastructure is crumbling.

They had a massive water main break earlier this year that made the national news.

Re:This is reassuring...

[JWSmythe]

    IANATE (I Am Not A Traffic Engineer), but I've had the opportunity to talk to some over the years. From what I recall of those conversations, most, if not all, traffic signals are failsafe. They cannot have colliding greens, and they won't generally just turn off. Even in the event of a power failure, they're suppose to stay up on batteries for a while.

    I have seen their failsafe behavior fail though. I was once driving on a dark foggy night. Visibility was very very poor. I was staying in my lane, but I couldn't see much else. I had a long drive in a rural area, and I was coming into an urban area. I expected to see street lights and traffic lights, but there were none. As I was driving, another car shot across the road just ahead of me, missing me by just a few feet. He didn't see the traffic light that wasn't working either. I called the police, so they could station an officer there. Their response was "Are you crazy? No one can see at that intersection. He'll get hit." Hmmm, good logic. At least no one got killed there that night.

And if they had been using roundabouts...

[macraig]

... to mediate traffic instead of traffic signals, they wouldn't have needed the aging old single-point-of-failure computer in the first place, because roundabouts (a) require no computers, (b) require no electronics at all, (c) require no electricity, and (d) don't require maintenance. What's more, since they allow motorists to preserve some momentum in all but the most congested traffic, gas consumption from forced arbitrary deceleration and acceleration is reduced. The only intelligence they require isn't of the artificial sort at all, only a smidgen of it from the motorists using them. They are un-powered and self-adjusting to traffic flow.

Would anyone like to take a stab at how much energy and man-hours is expended on the traffic signal network in the United States every year?

Re:And if they had been using roundabouts...

[Rick17JJ]

I have been very happy with the traffic circle which replaced the traffic light near where I live. It is on a two-lane highway in a smaller city here in Arizona.

I was very sceptical when the state said they were planning to replace the stop light with a traffic circle. But, the traffic circle has been able to handle the traffic much more smoothly than the stoplight did. I rarely need to wait more than a few seconds to get through the traffic circle, even during rush hour. I also usually do not need to make a complete stop, which saves gas and reduces the wear on my clutch.

As you mentioned, no electricity, computers or electronics are needed. It keeps working just fine, whenever the power occasionally goes off after a summer thunderstorm, for a few minutes.

Re:Report from the field: "Drivers very confused"

[Red Flayer]

If lights are aligned vertically, the red light is ALWAYS on top and the green one ALWAYS on the bottom.

Except for one light in Buffalo, NY.

The folklore is that the Irish workmen thought that green should always be on the top.

The light has been reaplced, IIRC, several times, but remains the only inverted traffic light in the US.