This is the "bridge" that I built last week. The two pipes are the water lines that run from the city well to the the water treatment plant. The new road that we were building crossed the pipes and they needed to be protected.
Despite this being a carefully engineered $6,000,000 project, there was no plan for how we should protect the pipes. We had lots of drawings and blueprints that showed every little detail of the road construction, but only one small note on the plans that said "protect pipe"
We looked around town for materials to use and found a big pile of 6"x12" timbers left over from an old tank farm project. We used these to field engineer a solution.
The first vehicle to drive over it when completed was that 40 ton dump truck that you see in the background. The bridge held up to that fine, so I think the typical village traffic of 4-wheelers and snowmobiles will be ok.