I spent part of this past weekend driving Iowa’s county roads, which is one of the best ways to discover that you can go a long way in Iowa without actually getting anywhere in particular. There are gravel roads, farmsteads, cornfields, curves apparently designed by someone who enjoys surprises and, occasionally, little signs that tell you exactly where you are. Those last items — Iowa’s mile markers — are considerably more interesting than they look.
For starters, Iowa’s mile markers aren’t really there to tell you how many miles you’ve traveled. They are primarily a location-reference system used by the Iowa Department of Transportation, and they aren’t nearly as old as Iowa’s highways.
Iowa published its first official road map in 1919 and developed its numbered primary-road system in the 1920s. Before that, motorists followed privately sponsored auto trails, including the Lincoln Highway, with organizations erecting their own signs and markers. Eventually, there were so many competing markers that finding your way became more confusing than helpful. The U.S. highway system arrived in 1926, but Iowa’s current mileposting system didn’t come along until 1973.
Here’s the part I find fascinating: A mile marker isn’t necessarily a mile marker. Iowa DOT places physical posts at approximately one-mile intervals. But those posts can be as much as 1.04 miles apart. The department now more accurately calls them “reference posts.” So, if you pass Mile 100 and then Mile 101, don’t start yelling at your odometer if it doesn’t show exactly 1.00 mile. There’s a good reason for that.
As we all know, Iowa’s roads get moved, straightened, widened, extended, shortened and rerouted. If every marker had to be renumbered and repositioned every time a highway changed, DOT employees might eventually quit and move to a quieter state. Instead, the physical reference posts provide a consistent way to identify locations while Iowa DOT’s computerized system keeps track of the precise geographic locations. And those reference posts are remarkably useful. If you call 911 and say, “I’m on I-80 near Mile 112,” you’ve provided a whole lot more useful information than, “I’m somewhere near Des Moines.”
Emergency responders, law enforcement, tow truck operators and highway crews use the system to locate crashes, disabled vehicles, debris, flooding, pavement problems, construction, bridge problems and road closures. On Iowa’s rural highways, where an address or landmark can be miles away, that little roadside sign is essentially a street address.
Here’s another interesting fact: Mile marker numbers generally increase south to north or west to east, although each route has its own starting point. Mile 50 on one highway has no necessary relationship to Mile 50 on another.
So, the next time you’re driving Iowa’s roads and see one of those little reference signs, give it a second look. It’s more than a number. It’s Iowa’s way of saying, “You may have no idea where you are, but we do.” And after spending part of a weekend wandering Iowa’s back roads, I find that strangely comforting.
Have a great week, and thanks for reading.
Shane Goodman President and Publisher Big Green Umbrella Media shane@dmcityview.com 515-953-4822, ext. 305 |