Driveway drainage Idea?

[James "Cubby" Culbertson]

Hiya Folks, I live in the arid SW although recently it's feeling more like Ireland these days! Anyway, my house is at the end of a sloping (down) driveway. The driveway is made of 8" or so of crusher run compacted. Anyway, with the increased rains this year, the water is just running down the drive and pooling at the edge of the house and a new adobe wall I constructed (water + Adobe = Not Good). So I'm looking for ideas to keep this water away. I'm able to divert it to the west side of the drive and create a large dry well easily enough. I was thinking of digging a trench across the driveway approx. 18" wide by say 12" deep at the east end and sloping pretty significantly down as it moves west towards the dry well. I was thinking of pouring a 6" footer slab in the trench with 5" walls on either side, put a notch in the tops of these walls and putting in grating. My thoughts are I'd catch the water running down the drive and divert it to the dry well. Any thoughts on this approach? I'm not sure if a 6" footer and 5" walls are enough for vehicular traffic or even if this is a viable idea. A french drain is not an option. The rains fall heavy and the water is just surface water that flows quickly. Should I be thinking about creating a "web" if you will by pouring supports between the two walls (obviously with a pipe through it )? Something like this (looking from above):

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII II II II II II II II II II II IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII

(sorry, my ASCII art isn't the greatest).

Thanks much for any advice! Cheers, cc

[dpb]

After living on a hill in TN where the slope was also towards the house and it rains much more than in AZ (I'm guessing) altho I am now back in SW KS where it is also relatively dry (but flat), I'm thinking you're over-designing a solution for your problem.

I'd simply regrade a section of the drive to be slightly lower than the level and then make it run back upwards a short section before the entrance to the garage and house. Then, a simple grade across the drive will divert the water around the house rather than letting it pool. A gravelled area might be nice for a flow area to ensure it doesn't cut a gulley in a narrow location...that solution worked well in TN w/ quite steep slope and heavy rains and was relatively cheap and quite simple to implement.

James "Cubby" Culberts> Hiya Folks,

[James "Cubby" Culbertson]

I thought about that but the drive is relatively short which wouldn't allow for much grading without creating a "roller coaster" affect so to speak. I know darn well that I'll build this thing and it'll never rain again! Cheers, cc

[dpb]

...

How steep a grade and how short a drive? Doesn't need much, just enough that the water doesn't crest owing to inertia down the slope, but since you're not paved anyway, that effect is minimal.

If that still isn't feasible, I'd think you could accomplish the objective simply by pouring a narrow section of concrete across the drive at an angle to be a solid barrier and thus divert the water when it hits the barrier. A couple of those could even diffuse the collection point(s) so not all is concentrated in a single stream.

That's similar to your grate, but less expense--in essence it's a one-sided channel where you've proposed a full-blown canal. Where the problem is intermittent at worst, still seems like overkill to me to go much more than that...

[Lou]

Is there any way you can waterproof the lower part of that wall?

Lou

[Bob]

How about digging the trench, laying plastic drain pipe in it, and covering it back to the surface with sharp gravel. You could even lay a steel drain grate on the top before the last gravel to hold the gravel in place.

Bob

[James "Cubby" Culbertson]

Thanks for the suggestions! If I can do this relatively cheaply, I will!

I haven't measured the drive but it's probably around 80 ft long. The problem I have is at the end of the drive, it levels out. So all the water I'm getting is coming from the drive itself. It levels out a bit as it enters the garage. I suppose I could try to re-grade it and I'll look into that. I'm worried I'd have a "speed bump" in the middle of the driveway though. Your suggestion of concrete diversion dams sounds intriguing but again, I'd be worried about them being speed bumps or I may be misunderstanding your suggestion. Thanks for the help! cc

[dpb]

...

That's essentially the situation I had in TN. All you need is to have the point roughly 5-6ft in front of the garage slab 2" or so lower than the slab. That will be enough of a barrier the water won't run into the garage and with just a slight slope to the side as well it will simply run off rather than pool.

It doesn't need to be a sharp drop or even very large so there really is no need to have a severe grade change, hence no bump.

The diversion dam I envision would be at the height of the gravel surface and would utilize the porosity of the gravel surface rather than creating a dam above the surface. If the surface is packed extremely tightly that might not work, but I inferred it was relatively decent-sized stone. The only issue I would see might be the gravel might gradually want to move downhill so you might occasionally have to grade it back out, but in that case it would seem to be an issue w/ the more extensive system as well...

I really can't envision a reason there couldn't be sufficient room to make a catch trough that would essentially eliminate the problem...

[Phisherman]

I have a sloping down double driveway and when we get heavy rains it looks like a waterfall. At the bottom and off to the side I installed a drain box and connected a tube that runs around the house into the backyard. It works well and carries off the water quickly---no more problems. I clean out the box once a year--usually about an inch of dirt collects there. You can do something similar. Look at the driveway edge and find the wettest area during a rain storm---that's where you want to install the drain box. The problem with putting in a grate is that some women have narrow high-heel spikes.

[James "Cubby" Culbertson]

The problem is I'm trying to divert it before it hits 5-6 ft in front of the garage. And 2" won't be enough. Our rains here are not light rains but heavy downpours that just wash down over anything without soaking in. We're famous for our "Flash Floods" here. I'm definitely going to take your advice and look at other alternatives vs. pouring all that concrete. I wonder if pre-cast is reasonable. Of course not, what was I thinking! Cheers, cc

[James "Cubby" Culbertson]

I suppose. I do plan to do some re-grading around the wall to help but my house foundation is right there too. And the way it's been raining, it may just make it's way into the garage too. cc

[James "Cubby" Culbertson]

The rains come so quickly here that it'll just roll right over the gravel. I've got french drains else where and they still flood. The areas dry out faster but there's still the flooding. cc

[ameijers]

Before you start building forms, check out the prefab drains at your local concrete specialty products dealer. They have those in plastic and slotted galavinized culvert pipe now. With whatever you use, I would plan on at least a couple of feet paved up top, to reduce gravel being washed in.

aem sends...

[James "Cubby" Culbertson]

Was this box something you got at a place like HD/Lowes or is it a specialty item? That may be a possibility. Thanks.

[Phisherman]

Yes. I bought the box at HD, no specialty item. I suppose Lowes would carry them too. They had two sizes and I bought the larger one with a removable non-breakable nylon grid on top.

[James "Cubby" Culbertson]

Thanks Phish. I'm starting to lean more and more to this idea. I have to figure how I can regrade the drive but I think I can do that. I intend to put down a couple of inches of crusher fines anyway so might as well do the whole enchilada! Thanks much. Cheers, cc