In-ground downspouts

[OneStaple]

Hey All,

My property (northern Virginia) has some slope and the five current gutter downspouts go into the ground with corrugated pipe to dump out down the hill (20-30' away from the house). Some of the gutters seem to continuously back up and spill over, even after the gutters have be cleaned and the vertical downspout sections checked. I suspect there are clogs and/or crushed sections within the buried corrugated pipe. No, I haven't tried snaking them and realize that this might be a good step to take.

Now, I'm on the verge of starting a deck project that will include laying a significant concrete slab (~12' x 40') under and next to the deck. Doing so would encapsulate one of the spots where a downspout goes into the ground, roughly half way along the 40' edge. I'll likely also need to create another downspout on one of the deck posts as part of the rain collection system to provide dry under-deck space, so that would be a second downspout going into/under the slab, but much closer to the edge. As such, I'd really like to completely fix my current in-ground drainage rather than just trying to patch it up or unclog it for now.

My plan is to move to 4" smooth-walled PVC. If it'll go through and under the concrete slab, what precautions do I need to plan into this? I assume the PVC should be at least below the concrete, but also the gravel that will be under the concrete? I understand that I'll need to provide slope for the pipes.

I figure there's about 170' of trench to dig to replace all the corrugated pipe. I'm debating whether this should be DIY or hired out, as that's a whole lot to dig. It's tough to find ballpark pricing for a job like this online. Any guesses? Only thing I could find was a website estimating $25/linear foot. Accurate?

Thanks,
Tyler

[chrisntam]

I just did this at my mom's house, (but through soil (and tree roots) only) I hand dug about 70 to 80 feet of trench.  Looking back, I'd prolly rent a trencher next time.  I ended up using 4" thin wall "Charlotte" pipe, 10' sections with one end "belled" to take the next section of pipe.  I used silicone sealer to seal the connections.  I put screening at the downspouts to prevent leaves from entering the underground drain line.  Material cost for my job was about $200.  In Dallas, $20 to $25 a foot were the estimates I was getting.

Here's a link to my thread:

https://forums.woodnet.net/showthread.php?tid=7353320

[Bob10]

I did mine with large schedule 40 pipe which can handle a sewer auger if needed.  As for digging the trench I used large yellow Bosch Jackhammer with a spade bit.  Made for easy work relative to what it could have been

[Splinter Puller]

I did mine with large schedule 40 pipe which can handle a sewer auger if needed.  As for digging the trench I used large yellow Bosch Jackhammer with a spade bit.  Made for easy work relative to what it could have been

+1 use a heavier pipe where you can't easily get access to it by digging.

[chrisntam]

As you can see by the pics in the other thread, all the pipe that I laid (wow, I said that in college) is easily accessible.

[OneStaple]

Thanks for the thoughts, all. chrisntam, your thread is helpful to read through.

I'm seeing a lot of mixed opinions on what type of pipe to use. The argument for SDR35 is that it's able to flex more with the ground, even though it sacrifices wall thickness to achieve that. Schedule 40 is beefier, but also more rigid and could potentially crack if the ground shifts. My house was built 40 years ago, so I think the ground has pretty much settled by now. The cost difference between the two isn't very significant, so I'd rather go with whichever is better. I'm not concerned about weight or connections.

If I were to go the beefy route, why not just do schedule 80 everywhere? I guess perhaps because it appears to be 3x-4x the price, based on some quick searches.

Thanks,
Tyler

[chrisntam]

Talk with the manufacturers to see what they recommend. Also consider how long you may live at that location when choosing materials though I buy the best I can.

[chrisntam]

You got those in ground drains done? You went silent for about 5 days, clearly that’s long enough to get the job done. (Wink wink).

It took me a looong time.

[OneStaple]

You got those in ground drains done? You went silent for about 5 days, clearly that’s long enough to get the job done. (Wink wink).

It took me a looong time.

HA! About the only project I've ever been accused of finishing that quickly is changing light bulbs, especially with two little ones consuming most of my time.

And my garbage disposal decided to start leaking and require replacing the other day. And my fridge is currently giving me issues (tonight's project…I think I know the issue). I'm now suspiciously eyeing all the other appliances. I think they're revolting.

Realistically, I'm still doing a lot of planning, especially since this is part of a much bigger deck replacement project. I want to make sure I have my ducks in a row before doing too much. And nothing about digging those trenches excites me.

Going back to your earlier comment, I generally like to use the best practices/materials and pay a bit extra for them, within reason. We'll likely be in this house for a while (5+ years), and we've already been here for 11. Not necessarily a forever home, but no plans to move either.

Tyler