[antidisestablishment]

When I lived in Minnesota, we had a dirt road in front of our farm that was pretty swampy. The county came out to fix it, and when they dug a few feet, they found the road was comprised of buried logs. The farmers had laid hundreds of logs perpendicular across the road and then filled over with aggregate.

The logs were ancient, but perfectly preserved from the anaerobic environment. The county just replaced the aggregate and left it, otherwise it would have cost $$$ to stabilize the muck. Sometimes we over think and over engineer things...

[kearnyirish2]

That’s a “corduroy road”; occasionally we have droughts here in NJ and when the reservoirs are low some of those old roads are uncovered (the old towns were drowned when the reservoirs were created). Near Giants Stadium we have a “Paterson Plank Road” through the Meadowlands which supposedly derived its name from that a couple of centuries ago...

[21twelve]

Where I live they are called “corduroy” roads (like the pants). I watched some show on building the Alaskan Highway during WWII. They would use this method to get across the swamps. At first the bosses thought the worker's weren't putting in the work and lying about it. They would say they put in 2 miles of road, but only 1.5 miles was in.

Turns out the muck was too loose in spots and the trees would sink in - so they added more trees and I think latched them together somehow. I would imagine those trees are still there as the road base. There is a road near me that was built like that back in 1908 or something and it is still okay.

[meatloaf]

I know of a dam that was built similarly in the 1800s. It was built with alternative layers of logs and rock. It worked well enough to collect water to run an undershot driven grist/saw mill.