Interstate 29 north approaching I-129 at Sioux City, Iowa.
For those who wonder, including ourselves, as to why signs along Interstate 29 northbound at Interstate 129 reflect the spur in text, I have an answer. At first, I speculated that Iowa wanted nothing to do with Nebraska’s Interstate 129. The fact of the matter is that there are signs for Interstate 129 on Interstate 29, half of which do not use the shield, but only an end sign along Interstate 129 east in Iowa and no signs at all along westbound.
So what’s the deal? On a whim I wrote IowaDOT about it the other night and received a response:
We received your comment concerning the use of the interstate shield for I-129 for southbound traffic and the use of letter text for I-129 for northbound traffic on I-29.
Approximately 10+ years ago some motorists were getting confused with I-129 signing, thinking it was I-29 and taking the off ramp to US75 to Nebraska when they really wanted to stay on I-29. We thought we would try using the letter text I-129 to make it stand out different from the interstate shield of I-29.
Since then we have had a signing project on southbound I-29 and changed the letter text I-129 back to the interstate shield and have had no complaints or concerns that I’m aware of. The northbound signing on I-29 will be reviewed when we put our next project together.
Thank you for you comments.
That’s a fair enough reason as any, and its only less road mystery to be solved.
Perhaps this was the same reasoning for Interstate 126’s text signs in Columbia, South Carolina…
oh that was interesting! we should write DOTs more often.
But how can that I-129 argument hold water when there are signs elsewhere in Iowa for Business loops (such as those on I-35)? Wouldn’t the green sign for Business I-35 be just as confusing as I-29 vs. I-129? Sounds like the logic of a pancake.
Although I didn’t get it in writing, conversations with SCDOT a number of years ago confirmed that the text signs for I-126 on I-26 eastbound were for the same reason: confusion with the mainline interstate. (Before the text signs, there were signs that had the “I-126” removed and read US 76 EAST with I-126 totally absent.) There is some justification in the I-126 case since the I-26 EAST roadway continues as I-126 and I-26 itself exits to the right. The confusion is compounded by the fact that even many locals call I-126 I-26. (I remember a wedding invitation with directions that stated that “I-126 is what I-26 is called within the Columbia city limits.”) It doesn’t help that TO I-26 and TO I-126 signs seem to be used interchangeably in downtown Columbia and that a resigning a few years back replaced a large overhead sign on westbound I-126 with “I-26/US 76 WEST.”
I suggested to SCDOT that a clear “identity” be given to I-126 by giving it an exit number off of I-126 and by posting exit numbers for its own interchanges. I claim no credit but the exit is now 108B off of I-26 but as of May 2007 there are no exit numbers on the road itself.