Putting in a gravel driveway

[future_vision]

A culvert and ditching would assure good drainage. A wide ditch or swale would be easy to maintain.
I would put in at least a 16" culvert, not because of flow but because it will silt up and fill up some over the years and the larger culvert will go longer between cleanings and is actually usually a bit easier to clean out.
Also the double wall culverts with the smooth insides are much better then the single wall corrugated things.

How far below the surface of the finished driveway should the to of the culvert be?

 

[paulsharvey]

How far below the surface of the finished driveway should the to of the culvert be?

12" Minimum coverage, over the top of the pipe. So, if you are placing 12" of base rock, at a min you want the full thickness over the pipe. It looks like that will not be an issue. If you are placing the pipe in that dip area; what I would do, I would place the pipe, and back fill 12" Over the top, before placing the 12" of base rock; for a total of 24" coverage, and that will take a significant chunk out of your dip. Keep in mind, that pipe is going to need to be absolutely 24 ft long, and depending on how they sell them locally; I'd buy a 30 or 32 ft long one. Your going to want a 4:1 maybe get away with a 3:1 slope on that embankment fill, if we are skipping the retaining wall idea.

So, let's say we use a 15" pipe, +12" fill, +12" base=3'6" we have picked the road surface up from the existing ground level at the dip. Nope, it's not the fill 6-7 ft, but it's half of it, and that will IMO be good enough

 

[Midniteoyl]

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

That's a good price. Around here, just using the truck by truck pricing not the 'whole job' quote, it would be ~$13200 delivered direct from the quarry. Add $2500 if using one of the 'gravel guys'.

 

[future_vision]

12" Minimum coverage, over the top of the pipe. So, if you are placing 12" of base rock, at a min you want the full thickness over the pipe. It looks like that will not be an issue. If you are placing the pipe in that dip area; what I would do, I would place the pipe, and back fill 12" Over the top, before placing the 12" of base rock; for a total of 24" coverage, and that will take a significant chunk out of your dip. Keep in mind, that pipe is going to need to be absolutely 24 ft long, and depending on how they sell them locally; I'd buy a 30 or 32 ft long one. Your going to want a 4:1 maybe get away with a 3:1 slope on that embankment fill, if we are skipping the retaining wall idea.

So, let's say we use a 15" pipe, +12" fill, +12" base=3'6" we have picked the road surface up from the existing ground level at the dip. Nope, it's not the fill 6-7 ft, but it's half of it, and that will IMO be good enough

Thanks. What would you back fill with in this scenario? I do have some non-organic material that I could use. Would you back fill some of the dip first and then the pipe followed by more fill and then the the bank run gravel?

 

[future_vision]

That's a good price. Around here, just using the truck by truck pricing not the 'whole job' quote, it would be ~$13200 delivered direct from the quarry. Add $2500 if using one of the 'gravel guys'.

Good to hear. I've been looking into renting a dump truck and pick the stuff up myself. But 23 loads is quite a few to get done in one day. If I could get 23 loads done that would probably save me $1300-$1500 if the rental is $800/day. Of course it would be less than 23 loads is I don't go with 12" of base layer.

 

[sixdogs]

Lots of comments and opinions so let me offer one thought everyone will agree with. Spend the money and put a great base in. It can be some rocks and then lots of bank run gravel and make it deep and wider than you think.

A good--no great--bulldozer guy makes a huge difference and knows what to do. We did three gravel drives in Maine. I did the first, had help on the second and got a great dozer guy for the third. That was the best.

Oh. don't drive down the center all the time but drive off-center to avoid ruts. And a rock rake in the spring will do a great job leveling things while a blade will create more problems than you want.

 

[future_vision]

Lots of comments and opinions so let me offer one thought everyone will agree with. Spend the money and put a great base in. It can be some rocks and then lots of bank run gravel and make it deep and wider than you think.

A good--no great--bulldozer guy makes a huge difference and knows what to do. We did three gravel drives in Maine. I did the first, had help on the second and got a great dozer guy for the third. That was the best.

Oh. don't drive down the center all the time but drive off-center to avoid ruts. And a rock rake in the spring will do a great job leveling things while a blade will create more problems than you want.

What were the issues you had doing it yourself? I've got nearly the entire drive, minus the dip area, level down to the non-organics. All measured with a rotary laser. I am curious what a professional would do differently?

 

[paulsharvey]

Thanks. What would you back fill with in this scenario? I do have some non-organic material that I could use. Would you back fill some of the dip first and then the pipe followed by more fill and then the the bank run gravel?

I would set the pipe at the bottom, add your no organic material to the top the pipe, compacting as you go. Then do your road bed.

 

[Too many Kubotas]

12" Minimum coverage, over the top of the pipe. So, if you are placing 12" of base rock, at a min you want the full thickness over the pipe.

Uh, oh. That sounds like the little 12" culvert I just lengthened won't make it.

Well, I'm not worried. With a few culverts like that, all of which have survived so far, it might live.

After all, the 24" one that has supported dozens of fully loaded end dumps and other machinery over the years is alive and well, with about the same amount of fill above it.

 

[paulsharvey]

Uh, oh. That sounds like the little 12" culvert I just lengthened won't make it.View attachment 980854

Well, I'm not worried. With a few culverts like that, all of which have survived so far, it might live.

After all, the 24" one that has supported dozens of fully loaded end dumps and other machinery over the years is alive and well, with about the same amount of fill above it.

Not saying less coverage will immediately crush, but 12" of coverage is generally spec'd by any public works/road department, and is a good guideline. Our OP has the ability to get the coverage, and frankly it helps his dip problem, so coverage is his friend.