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Another Boondoggle: Variable Speed Limit Signs

Springfield Interchange

When you refuse to increase highway capacity at the rate of population growth, all sorts of hair-brained schemes to reduce traffic congestion emerge. Here’s the latest.

The Virginia Department of Transportation (V-DOT) is erecting new speed limit signs with digital readouts. According to the new scheme, traffic engineers will be able to change the speed limits on these new signs – higher or lower – depending on congestion, construction, or whatever else they deem worthy of changing the speed limits.

According to John Undeland, a “project spokesman” (a position that should be eliminated immediately) for the never-ending construction project on the Woodrow Wilson Bridge,

By regulating the speed we actually get a lot more vehicles through and a lot more safely …

The Wilson Bridge spans the Potomac River between Alexandria, Virginia, and Oxon Hill in Prince George’s County, Maryland. It serves as a major chokepoint for I-95 and I-495 (the Capital Beltway). The bridge is in a never-ending state of construction, and traffic is consistently horrible at peak hours.

Let’s analyze what Undeland is saying. When the Wilson Bridge gets jammed with cars during morning or afternoon rush hour, which it always does, and traffic slows to a crawl, he thinks that “regulating the speed” is going to reduce congestion? How does that make any sense?

Think about it. You’re driving at 5 mph. You can’t go any faster because there’s cars in front and behind you all going 5 mph too. How does raising the speed limit to 10 mph or reducing it to 3 mph on some digital sign have any effect?

Undeland also discusses traffic congestion at the Springfield Interchange, where traffic from three major highways, I-95, I-395, and I-495, collide in a tangled, disorganized, spaghetti mess, and congestion during peak periods is a given:

So the speed limit may be 55 at the Springfield interchange, [and] it’ll go down to 50, 45 and so forth …

This is laughable. 45 mph during rush hour would be a gift from heaven. The reality is that traffic is never 45 mph during these times, or 40, or 35, or even 30 mph. Cars move at a slow, pathetic, measly crawl. Everyone just sits there and deals with it. Adjusting a digital readout on a speed limit sign won’t have any effect.

So now that we’ve established that variable rate speed limit signs are stupid, let’s talk about the costs of this stupidity, which we’ll all pay through our income taxes, or various surcharges, fees, and fines.

There’s the cost of the new digital signs. There’s the cost of the traffic engineer slugs who’ll sit and monitor the signs and adjust the digital readouts. There’s the cost of the government administrators who’ll manage the slugs and collect metrics on this scheme. There’s the cost of the administrative overhead. And on and on and on and on and on. In a few years, we’ll have an entire floor of government cubicles in some large high rise devoted to managing this buffoonery.

The best part is that, in order to sell this stupid scheme to Virginians, the officials at V-DOT have crafted a little metaphor:

If you pour a bag of rice all at once into a funnel, it clogs and stops the flow. If you pour the rice at a measured pace, no clogs.

I have a metaphor of my own:

If you give a bag of rice to a bunch of stupid government officials, they’ll eat it right in front of you, and demand more.