Wet weather spring in driveway

Buppies · Mar 19, 2012

By the way this parking lot that is referred to has water running out of the drainage pipes 365 days a year and has constant truck traffic 5 days a week

EddieWalker · Mar 19, 2012

Randy,

I'm sure the parking lot that you mention is working just fine. I don't think it has anything to do with this project, or what was done there compared to what was done here. By nature, a parking lot is going to be faily level, it was probably designed by hydraulic engineers with a budget that probably exceeds the entire price of the land in this thread. Heavy equipment was probably used to remove and bring in materials that are cost prohibitive on a project of this scale. Those materials where worked with a final design that was done in stages so as to create a compactable surface that would never shift or settle.

While I don't know all the details, I do have some experience with parking lots, dirt and drainage back in CA. Not sure where your parking lot is, but we worked with inspectors and plans. Creating a massive french drain is NOT how to buld a solid base for a road or parking lot.

The picture with all the water in the hole shows why this was not the way to fix this problem. The ground containes a certain amount of moisture per cubic foot. Once that hole was dug, that area now contains 100% water per cubic foot. I don't know what the percentage was before, but making it one hundred percent made it a lot worse!!!!

At that point, the only options was to either fill the hole with a solid plug or moving the road to another location. The plug could have been a high quality fill material or concrete. Never gravel. The idea of the plug is to create a solid base for the road and force the water to other areas. Water only has so much force, so it will either sit still or move to the area of least resistance. A plug would have forced the water somewhere else, or kept it out of the area for the road. Either way, the results would have been acceptable.

By creating a place for the water to go, it will never stop going there.

Eddie

Buppies · Mar 19, 2012

Mr. Walker since you don't know the facts in this case it was a southern states distributation center. The area in question was prepared using a backhoe and skid loader and by the way the only engineering done on this project was done by our grading manager who got his degree through the school of hard knocks. My only point here is to say that the op did a great job not to say what he did will fail which I do not believe it will. Enough said by me.

nrc17gto · Mar 31, 2012

Ok, so this is as close to the finished product as it is going to be for a little while. I will figure out what to do with the ditch sometime this summer. Thanks again for all the help everyone.

DrivewayFixed by nrc17gto, on Flickr

Nick

Mistyridgefarm · Mar 31, 2012

You did a good job! Here in TN, this situation is very common. The farm I bought has a paved driveway going up a hillside. The center section was heavily damaged. I made temporary repairs with crushed stone until I could figure out what was the reason.

Well, the area was firm until the following spring, when weeks of rain made several springs appear. The top off the hill has pretty permeable soil. The water is seeping in very well but there is a clay layer, impermeable, about 80 feet down. That strata just happens to be the part the driveway crosses about half way up. The hydraulic pressure hits the clay layer and pushes out the side of the hill.

First, they didn't put a very good base under any of it. That would have helped. Second, they should have known what would happen when the driveway was cut in, when they went from chert to clay and back to chert. I'm sure it all looked real pretty the first year or so.

I sloped both sides of the road to make ditches about 2 feet lower than the bed and a good ten feet from the sides. This helped let the water that was pushing out drain away from the road bed.

This worked pretty good this spring so far. I am also going to go about ten feet in elevation from the top of the clay layer and cut a hoe width trench across the hillside and run it laterally until it hits the normal grade. Then the trench will be filled with crushed rock, basically making a French drain so the water pressure can be relieved away from the road. I will do this soon and then rebuild the road bed and have it repaved. Should be good to go after that.

Moral of the story- consultation with a hydrologist or at least a very experienced road builder will save you or the next person a bunch of trouble!

The OP looks to have a similar situation but his road is side hill crossing. The rock and drain should give somewhere for that water pressure to go, and let the area firm up. I wish you the best of luck!