I have a new roadway going up a 9% grade and I am required to shed the water off the surface of the roadway in one of several possible ways. The roadway is crowned, but due to the steep grade, it would allow the water to run down the roadway too far, so it needs help being directed to the ditches. The Soil Engineer has been really good, and we are trying to really build a road that really works. Everything about this project has been great...until now. Now I cannot see how to do this requirement and still be really functional.
Broad Based Dips: Obviously they are great because they are easy to build and the material is free, but this is a 4 season road with heavy haul trucks and rolling over (4) broad dips is going to break springs! Also I clear this road in the winter with a bulldozer so in a years time I am most likely going to bulldoze the rolling dip out of existence. Bulldozers are meant to push flat and smooth and do not do bumps well.
Rubber Razors: Honestly I am having a hard time finding material to make this. I can buy new rubber belting but it is super expensive to get custom made, and used belting is cheap, but only by the foot. I really do not need 400 feet of four foot wide belting for anything. Also, bulldozing the snow in the winter will shear the rubber right off the razor!
Open Top Culverts: This is the one we are considering right now, and it has a lot of merit. I can plow over it without digging it up, it is cheap to build, trucks will not break springs, but I am pretty sure I am going to just fill it with sediment when I bulldoze snow all winter. At the same time I am not sure how a plastic culvert so close to the surface, or a U-shaped wooden set of planks will do with a bulldozer driving over it? My bulldozer spreads its weight pretty well (unlike my ex-wife), but with its 3 inch grouser in the right spot, it might destroy the open top culvert in short order.
What say the experts on this tough earth works problem?
I am o sorry, yes I went with Broad Based Dips because winter plowing would mean destruction of whatever I put down, and I could refresh the broad based dips without cost, unlike the other items.
This is what it looks like after completion. You can see the broad based dips start on the right side by each rock dam, then traverse at a 30 degree angle across the road to terminate at another rock check dam.
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