I work in the freight and shipping bidness, and one of the recurring gripes that I hear from drivers has to do with the signs shown above.
The left lanes of Fort Worth's Interstate-30 were closed off to "trucks" a couple of years ago. This was supposedly done to improve traffic flow.
But, as one of my mentors recently told me, "if you ain't got the data, the chatter don't matter".
Words to live by.
Does this restriction make a demonstrable difference?
According to a study presented in (ahem) College Station, TX.... completed at a cost of $960,000.00..... and this doesn't include the cost of the signs or their installation....traffic has averaged a 1/2 mile per hour improvement.
Interstate 20 and Interstate 30 both got the signs and restrictions, and the data from both highways is lumped together as one number in the presentation.
Why? I'm betting that one of the highways had a meaningful improvement in speed, and the other one stayed the same or even declined.
But lets look at the methodology for a moment. The study compares what they call Phase 1 (August) to a similar time period in Phase 4 (January/February). Can anyone else in the trucking business (I don't want to be the spoiler) let us know how much difference there is in freight volume between August and January/February?
We're not comparing apples to apples, or even apples to coconuts. It might not even be apples to alligators. It's huge.
And a 1/2 mile per hour improvement? (Unless I'm mistaken, the decimals are rounded upward from here to here.) I think we're looking at static, white noise, and dissimilar time periods. These numbers aren't significant enough, in my opinion, to show us anything outside the margin of error.
Who is more likely to hop onto an interstate highway for just a few miles? The guy in a two-door compact, or the long-haul trucker? The left lane should be for those who are just passing through. Those going from exit to exit for a few miles should be in the right lanes. And they don't need 18-wheelers in their way.
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