Ryan, Cool pics!. My best guess (read: stab in the dark with sunglasses on) would be that the Corrugated Steel that makes up the culvert lining, collapsed under the wieght of the road above. After all, you'd think there would at least be one or two supports underneath it.
Re: OT: Water culvert failure#120657 04/29/0507:09 AM04/29/0507:09 AM
This is the E-mail my brother sent me along with the pics.
Check out the attached pictures of a failed culvert (a.k.a. stockpass and/or tractor pass) out near Glendive along I-94, it failed in the driving lane of the westbound side about a week ago. It was somewhat corroded and just collapsed in.
Luckily, a tow truck driver saw it and was smart enought to turn on his lights and stop traffic so no one would drive into the hole.
I think Walrus is right, it must be an animal/equipment crossing thing. (I'm a city dweller, I don't know! )
Ryan Jackson, Salt Lake City
Re: OT: Water culvert failure#120659 04/29/0510:43 PM04/29/0510:43 PM
Now that walrus mentions it, that's what this thing is for. We have them over here, they are called stock underpasses. Good thing that this happened during daylight hours, at night with no adjacent street-lighting could have made things a different story.