Putting in a gravel driveway

[dodge man]

I have seen field tile type pipe installed alongside highways on Illinois. Usually where there is high ground alongside the highway that would force water into and under the highway. I wouldn’t do along side the driveway. If you can drain the water across the driveway that will work, part of mine is that way. This works as long as it’s not concentrated in areas which would cause erosion.

 

[paulsharvey]

The ground does slope from the high end of the driveway to the low end naturally and all the way to the back of the property. That is still the case unless we back fill some of that area which we might. Even backfilled there should still be a slope.

One of my thoughts, that wouldn't involve a culvert is to build up the high side until it is level with the rest of that side of the driveway. Then the entire driveway is level. Then handle water management either by pitching the entire driveway so the water sheets off to the low side. I was also thinking that if I went with a crown I could bury perforated pipe, wrapped in fabric, to both sides and move water that way. I've not seen it done that way before but it was a thought similar to what you would do along the foundation of a home.

I don't like perf pipe, it gets clogged, and had a way of moving when placing material and back filling.

 

[paulsharvey]

I would think that is too low though. If the bottom of that dip is 7' lower than level with the rest of the driveway, and I already have material to either side, I would think I'd need to be at least a couple feet higher wouldn't I to keep the culvert fro being buried? Or maybe you are thinking I need to remove material on both sides to create a path for the water?

See right below, LouNY is 100% right.

I took the liberty of drawing the world's most primitive Plan and Profile sheet. So, assuming we don't want gravity walls/retaining walls; the red lines on the cross section are a mild fill and mild dip, with the plan sheet slope shown in black, as with the pipe show in black on the plan sheet.

If we want to remove the entire dip, see the blue lines on both the plan sheet, as well as the matched profile/cross section.

 

[paulsharvey]

As I hope I showed, by adding the additional fill; we have by default lengthen the needed pipe.

12 ft roadway; 15" pipe, and 12" fill and 12" rock; we need a pipe; we need 38 LF of pipe. (at 4:1)

12 ft roadway; 15" pipe; 24" fill; 12" rock; we need 46 LF of pipe (at 4:1)

If we have 15" pipe; 48" of back fill; and 12" of rock; we have a total rise of 6'3" and that means each end of the pipe needs to account for an additional 25LF of pipe (keeping a 4:1 slope) or 19 LF if using 3:1. For a total length, of 62 LF using 4:1 or a 50 LF if using a 3:1 slope.

 

[paulsharvey]

A 60 LF 15" CMP is going to come as 2 sections, so you also need a coupling band, and I'm guessing band, and 60 LF, we are probably over $2500 for a pipe that long.

 

[paulsharvey]

So, looks like 15" CMP is around $550/20 LF, and coupling bands are at $40/each.

Kinda all boils down to $$$.

 

[paulsharvey]

Now; ill throw another thought; you can always try to retaining wall approach and vertical sides; and add additional backfilled slopes and pipe extensions in the future; but it will be harder to get in there, and likely the outside of your roadway will "sluff" off some; but it's not that expensive to retro fit. It might just work; but I'm betting against it, with a 7 ft fill.

If you truly want to take that approach, consider doing something similar to an MSE wall; mechanically stabalized earth; were in your case, you would have SS cables, or rods, or something that connected both walls, E and W, and went through the embankment, to keep everything from shifting and putting outward pressure on the walls. I dont like this approach, as it's complex, adds cost, and frankly; dirt is cheap, and there is an engineered design to eliminate the need (minor dip at this location).

 

[ning]

Yep. Gave them what I was looking for. This is the full quote:

What I can tell you is if your driveway is 600'Lx12'W and your garage area is 38'Lx55'W and you want 1' Depth of road base (4"minus bank run gravel) you would need 412CY of material.
412cy (4" minus bank run gravel) x $15.00 = $6,180.00
Delivery = 23 loads x $115.00 = $2,645.00
TOTAL = $8,825.00

I assume there's slop in the calculations to account for settling & compaction?

Because (600*12 + 38*55)/27 = 344 cy (estimate is 20% higher still)
and if we go a foot wider on the edges everywhere (just throwing this out there, assuming that you have 12' of good width and then that final foot ends up sloping more) then
(601*14+39*56)/27 = 392 cy (estimate is 5% higher still)

so I'm curious how they do the volume estimate?

 

[paulsharvey]

BTW, everyone has different things that bug them, so, if the dip or vertical curve is going to pass you off every time you use it, by all means, spend the money to remove it. A smooth, rounded, long vertical curve doesn't bother me.

 

[dodge man]

Paulsharvey drawing is exactly what I was talking about when I said a pipe in a low area. I was a land surveyor for a civil engineering firm for over 35 years and our plans looked like that just a little more official with an engineers seal on it.