Author Topic: Concrete pour - abandon irrigation or remove?  (Read 925 times)

jeromedawg

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Concrete pour - abandon irrigation or remove?
« on: January 17, 2022, 09:49:40 AM »
Hi all,

We are considering pouring concrete against the side of our house where we currently have an area of dirt. The goal is to keep as much water away as possible. Obviously have dirt/vegetation there isn't going to be conducive to that. One issue is that there is currently piping there for irrigation. And at least one line is an 'artery' that runs to the rest of the backyard. This appears to be a pretty old system and I'm suspecting there might also be leaks in various places. I'm thinking maybe it's best just to abandon? I've heard you can pour concrete over old lines but not sure if it's better/cleaner to remove them vs leave them there. Whether we remove at least this section of piping or not if we end up abandoning the system I'm thinking we also need to remove the old Rainbird timer and the manifold, all the old valves (these valves are leaky too), and the box that they're in before we cement around that area as well.

Any suggestions? I don't think I'm going to deal with the concrete pour (will likely hire that out) but I have a pair of PVC cutters and don't mind cutting some line. Just wanted to get some clarity on the best way to approach this...

markbike528CBX

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Re: Concrete pour - abandon irrigation or remove?
« Reply #1 on: January 17, 2022, 10:00:06 AM »
If the system was going to be used,  I definitely wouldn't concrete over it.  As you are abandoning it, rip out as mich as you can. Future irrigation installers ( you or whoever) won't curse as much.

jeromedawg

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Re: Concrete pour - abandon irrigation or remove?
« Reply #2 on: January 17, 2022, 10:41:21 AM »
If the system was going to be used,  I definitely wouldn't concrete over it.  As you are abandoning it, rip out as mich as you can. Future irrigation installers ( you or whoever) won't curse as much.

Yea it's tricky because this side of the house is where the water supply is:


So if we pour concrete we would likely never be able to run new lines anywhere after. Maybe pavers would be better? Or perhaps a combination of cement + pavers (where the pavers are sitting over the line)? If that's viable, then I'd probably cut and remove the existing portion of line in this area (it's split into multiple branches in various parts of the dirt strip (it's kind of all over the place)) and just do a long "L" and reattach so that the line running to the backyard could still be used. On one hand it feels like a waste not to have anything hooked up to this as they branched of a separate line for irrigation.

BudgetSlasher

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Re: Concrete pour - abandon irrigation or remove?
« Reply #3 on: January 17, 2022, 10:58:55 AM »
The absolute cleanest route would be to remove everything under the slab. Personally, I would probably remove the larger footprints (like the box and its contents) and leave the small items (PVC lines). When considering the slab.

If considering the irrigation system, I would probably still abandon under the slab and reroute. While I was typing you posted your picture and additional details. If I kept with the idea of concrete If there is a water to the system from a different point in your home that would be my first choice. Otherwise I would replace/upgrade the lines that will be under the slab; I would probably relocate the valve box somewhere outside of the concrete (though I seen them coming in the middle of a slab before).

Personally looking the picture I would be concerned about doing a concrete slab there. Here's why, depending on other water control, when water drops on concrete it is going to create a lot more splashback that other surfaces which is going to get the stucco wetter. If the stucco is not done perfectly that moisture is going to find its way inwards, as well as outwards, as it drys. I would explore the possibility of (and the right materials and methods for) digging that area out, installing a section of drain pipe, and backfilling with gravel/stone.

Take my opinions with a grain spoonful of salt, since I am a DIY guy who has not spent a lot of time with irrigation systems.



Fishindude

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Re: Concrete pour - abandon irrigation or remove?
« Reply #4 on: January 17, 2022, 11:22:54 AM »
Anything close to or above surface should be removed.   Anything below grade can simply be abandoned in place and poured over.
If you do decide to pour that strip full of concrete, make sure you have a nice slope away from the house.

jeromedawg

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Re: Concrete pour - abandon irrigation or remove?
« Reply #5 on: January 17, 2022, 11:48:51 AM »
The absolute cleanest route would be to remove everything under the slab. Personally, I would probably remove the larger footprints (like the box and its contents) and leave the small items (PVC lines). When considering the slab.

If considering the irrigation system, I would probably still abandon under the slab and reroute. While I was typing you posted your picture and additional details. If I kept with the idea of concrete If there is a water to the system from a different point in your home that would be my first choice. Otherwise I would replace/upgrade the lines that will be under the slab; I would probably relocate the valve box somewhere outside of the concrete (though I seen them coming in the middle of a slab before).

Personally looking the picture I would be concerned about doing a concrete slab there. Here's why, depending on other water control, when water drops on concrete it is going to create a lot more splashback that other surfaces which is going to get the stucco wetter. If the stucco is not done perfectly that moisture is going to find its way inwards, as well as outwards, as it drys. I would explore the possibility of (and the right materials and methods for) digging that area out, installing a section of drain pipe, and backfilling with gravel/stone.

Take my opinions with a grain spoonful of salt, since I am a DIY guy who has not spent a lot of time with irrigation systems.

Yea, I was first considering a french drain type system (with rock filling that area over it) but the problem with this area too is the section between the chimney and walkway - it's quite narrow at probably no more than a foot to foot and a half. There's footing under there that kind of sticks out - with the current drain that's there, it has caused it to "belly" in this location.

I had a drainage company come out to quote remediation of this and they wanted $5k to install a french drain but this would be the type where excavate around the foundation, apply waterproof membrane, and then lay the french drain right up against the side of the house. Sounds great but logistically, I'm not sure how that would work with the chimney area.

My idea would be to place the french drain in a straight run parallel and right up against the walkway. I might have to re-route some piping to go *under* the portion of walkway where the chimney is. I would also need to grade the dirt from the house down to this drain as well though. I'm not sure if we would also need to excavate dirt out of this area. If we were to go this route, I would probably just run the irrigation line right next to the drain or very close to it.

Good point about the water splashing off the concrete btw: I could see that happening and splashing back onto the stucco. I think the moisture issues we're currently having with our walls is related to the windows - seems the flashing is failing or insufficient. We recently had to rebuild the weep screed around most of this area of the home because the prior owners had it covered with soil and mulch so it had rusted out and there was damage from that. The issue with the leaky windows is just compounding the problem.
« Last Edit: January 17, 2022, 11:57:11 AM by jeromedawg »

lthenderson

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Re: Concrete pour - abandon irrigation or remove?
« Reply #6 on: January 17, 2022, 01:41:22 PM »
I'm not familiar with California building standards and stucco, but it puzzles me why you want a French drain in this area when you have said that the house is on a slab with no basement? If it is just a low spot collecting water, I could understand but then that would not make me want to put a slab in that area as it will just create a puddle between it and the existing slab with no way but evaporation to remove it. If it isn't collecting water, then I would just remove what you can above ground, grade the dirt to slope slightly away from the house, put landscaping fabric to block weeds and top with your choice of gravel or mulch and some local landscape plants if desired that meet shade/sun requirements in your area. Gives you the most future flexibility and probably the easiest access should you ever need to get underground in that area again.

jeromedawg

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Re: Concrete pour - abandon irrigation or remove?
« Reply #7 on: January 17, 2022, 04:12:38 PM »
I'm not familiar with California building standards and stucco, but it puzzles me why you want a French drain in this area when you have said that the house is on a slab with no basement? If it is just a low spot collecting water, I could understand but then that would not make me want to put a slab in that area as it will just create a puddle between it and the existing slab with no way but evaporation to remove it. If it isn't collecting water, then I would just remove what you can above ground, grade the dirt to slope slightly away from the house, put landscaping fabric to block weeds and top with your choice of gravel or mulch and some local landscape plants if desired that meet shade/sun requirements in your area. Gives you the most future flexibility and probably the easiest access should you ever need to get underground in that area again.

There's *supposed* to be a 4"-6" clearance from dirt to weep screed in general. The walkway sits almost level to the weep screed - when they repaired the weep screed they actually raised it by 2-3" to account for any grading. But even then, this spot is still problematic because of the height of the walkway. If we wanted to really do it right, we'd demo the walkway and rebuild it at a lower grade, but that seems like an expensive proposition. The problem I see is that if we excavate according to code, 4" will be too deep in relationship to the walkway -the level of dirt will be below the level of the walkway, so even if I graded, water would just pool up to the lip of the walkway then overflow from there. I think this is what the problem has always been. Obviously the drain is supposed to alleviate that except for the fact that it's limited on how deep it can go due to the chimney footing. Right now this is the most problematic area of the yard. The contractor who did our weep screed said that technically we can get closer to the weep screed because he waterproofed the siding under it and also added metal flashing as an additional layer of protection so even if water does pool up there it's not getting in the house easily. As long as it's somewhat graded to the point that water or dirt isn't going to cover the weep screed again (which was the original problem - previous owner covered the weep screed completely) it won't be a problem. Now, whether this would be to code or not I'm not sure. Since we're not planning on selling anytime soon (afaik haha) maybe we should take him at his word and ignore the code in this case.

Anyway, if we poured concrete here, we would still grade and slope it the similarly to how we would grade dirt. It's just that the cement would fill all the way to the same level as the existing walkway, which does have *some* grade to it. The thought is that, as long as the slab is sloped/graded away from the house and at the same level as the other walkway, the water will actually flow downhill and we can catch it with a drain/french drain/dry river bed/swale or whatever else on the *other* side of the walkway. But yes, I'd still be concerned with losing the flexibility of being able to run irrigation lines through this area in the future (not that I'd want to plant anything that needs irrigation here but more to provision for the backyard or whatever and being able to repair/replace anything that breaks)
« Last Edit: January 17, 2022, 04:24:57 PM by jeromedawg »

Paper Chaser

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Re: Concrete pour - abandon irrigation or remove?
« Reply #8 on: January 17, 2022, 05:24:51 PM »
If water getting trapped between the walk and the house is a concern, what about digging that section of dirt out to the appropriate height, pulling up the brick in the walk, grading the ground such that you could install drainage where the brick is in the walk, and then reinstalling the brick? Or just replacing the brick with a plastic French drain if the drain would be too deep? That would allow the water to drain out to the outside of the walk with minimal cutting of the walk.

Then, you'd have soil at the appropriate height in between the house and walk, but the walk would be a few inches higher. To bring up the height to match the walk and avoid trip hazards, you could fill that area with landscape rock. That would drain well, not hold any moisture, and keep the weep screed clear and uncovered without being permanent like cement. I guess in theory, you could turn the entire section of ground into a giant French drain with landscape rock being the medium that stays exposed while draining really well.
« Last Edit: January 17, 2022, 05:29:29 PM by Paper Chaser »

jeromedawg

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Re: Concrete pour - abandon irrigation or remove?
« Reply #9 on: January 17, 2022, 07:10:12 PM »
If water getting trapped between the walk and the house is a concern, what about digging that section of dirt out to the appropriate height, pulling up the brick in the walk, grading the ground such that you could install drainage where the brick is in the walk, and then reinstalling the brick? Or just replacing the brick with a plastic French drain if the drain would be too deep? That would allow the water to drain out to the outside of the walk with minimal cutting of the walk.

Then, you'd have soil at the appropriate height in between the house and walk, but the walk would be a few inches higher. To bring up the height to match the walk and avoid trip hazards, you could fill that area with landscape rock. That would drain well, not hold any moisture, and keep the weep screed clear and uncovered without being permanent like cement. I guess in theory, you could turn the entire section of ground into a giant French drain with landscape rock being the medium that stays exposed while draining really well.

I was mulling this over before the concrete idea was suggested (though I had thought of concrete before and the idea fizzled) but I came up with something last week that I *think* is close to what you're describing:


So what you're saying is to excavate dirt out so it's 4-6" below the weep screed, also grading it so it's sloped *away* from the home towards the walkway as well as southwest downhill of the property (since this is the natural grade), then fill that area up with landscape rock and use the brick area in the corner as the place to locate the drain. I was thinking it still *might* be useful to lay a perforated pipe french drain next to the length of the walkway to divert water faster towards the catch basin. I would do a piped french drain system there, through the brick, and then perhaps consider have it exit to a dry riverbed on the other side of the walkway to the catch basin (or I could continue the run of the french drain all the way to the basin). I'd have to create some kind of "step down" are where the catch basin is though, and envision possibly having a small 'waterfall' type of setup there so when water drains it's just pouring over and into the catch basin not too different from how it currently is setup.

affordablehousing

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Re: Concrete pour - abandon irrigation or remove?
« Reply #10 on: January 17, 2022, 10:42:06 PM »
You need to hire a true professional, Odell Complete Concrete. He's the friggin rockstar of concrete.

lthenderson

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Re: Concrete pour - abandon irrigation or remove?
« Reply #11 on: January 18, 2022, 08:40:09 AM »
There's *supposed* to be a 4"-6" clearance from dirt to weep screed in general. The walkway sits almost level to the weep screed - when they repaired the weep screed they actually raised it by 2-3" to account for any grading. But even then, this spot is still problematic because of the height of the walkway. If we wanted to really do it right, we'd demo the walkway and rebuild it at a lower grade, but that seems like an expensive proposition. The problem I see is that if we excavate according to code, 4" will be too deep in relationship to the walkway -the level of dirt will be below the level of the walkway, so even if I graded, water would just pool up to the lip of the walkway then overflow from there. I think this is what the problem has always been. Obviously the drain is supposed to alleviate that except for the fact that it's limited on how deep it can go due to the chimney footing. Right now this is the most problematic area of the yard. The contractor who did our weep screed said that technically we can get closer to the weep screed because he waterproofed the siding under it and also added metal flashing as an additional layer of protection so even if water does pool up there it's not getting in the house easily. As long as it's somewhat graded to the point that water or dirt isn't going to cover the weep screed again (which was the original problem - previous owner covered the weep screed completely) it won't be a problem. Now, whether this would be to code or not I'm not sure. Since we're not planning on selling anytime soon (afaik haha) maybe we should take him at his word and ignore the code in this case.

Anyway, if we poured concrete here, we would still grade and slope it the similarly to how we would grade dirt. It's just that the cement would fill all the way to the same level as the existing walkway, which does have *some* grade to it. The thought is that, as long as the slab is sloped/graded away from the house and at the same level as the other walkway, the water will actually flow downhill and we can catch it with a drain/french drain/dry river bed/swale or whatever else on the *other* side of the walkway. But yes, I'd still be concerned with losing the flexibility of being able to run irrigation lines through this area in the future (not that I'd want to plant anything that needs irrigation here but more to provision for the backyard or whatever and being able to repair/replace anything that breaks)

Thanks for the more detailed explanation. I think that makes a lot more sense to me now and I understand your dilemma. I really don't like having dirt, gravel or anything up next to house siding and try to have at least six inches of space. It sounds like you have the grade available if it weren't for the sidewalk that is poured too high. To do the French drain between the sidewalk and the house, you would still have to at least tear up a section or two of your sidewalk, or bore underneath, for your French drain to gravity drain to daylight and to do both sections, on either side of the chimney.  I also don't like concrete up next to a house. Even if sloped, it can splash water from a hard rain up quite a ways onto your stucco siding. Also depending on slopes, a hard rain can still backwash into the joint between the concrete and the house before adequate draining toward the sidewalk, especially if you would have to put in a really shallow slope to keep maximum distance from the weep screed.

As long as the sidewalk is below the top of your house slab level and below the weep screed level, this is what I would do. Dig the dirt in the area between the sidewalk and the house down about six inches below the proper clearance of the weep screed (10 to 12 inches in your case), put in water permeable landscape fabric and six inches of landscaping rocks so you still have your 4 to 6" clearance. Don't bother with the French drain at all. Any water collected there by rainfall, will essentially be contained in a reservoir between the surface of the dirt and top surface of the gravel until it can be absorbed by the soil below. (I'm assuming your soil can absorb water fairly well.) The gravel keeps it from ponding or allowing mosquitoes and such from laying eggs. It shouldn't affect your foundation since you have a slab and I'm assuming you have rain gutters above that direct water into downspouts on the far side of the sidewalk. This allows you access to it in the future if needed and it probably the most reasonable option money wise as well.  This is essentially a slow version of a French drain since you are counting on absorption instead of a pipe to remove the water and would be able to still work above and around your chimney footing. With your fairly dry climate, it should be more than adequate.

The other more expensive option would be to just have someone come in and take out the sidewalk so the entire areas can be graded properly with the proper clearances and put in some combination of concrete and pavers sloped the proper way and end up with a step where your sidewalk goes through the gate.

jeromedawg

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Re: Concrete pour - abandon irrigation or remove?
« Reply #12 on: January 18, 2022, 09:21:06 AM »
There's *supposed* to be a 4"-6" clearance from dirt to weep screed in general. The walkway sits almost level to the weep screed - when they repaired the weep screed they actually raised it by 2-3" to account for any grading. But even then, this spot is still problematic because of the height of the walkway. If we wanted to really do it right, we'd demo the walkway and rebuild it at a lower grade, but that seems like an expensive proposition. The problem I see is that if we excavate according to code, 4" will be too deep in relationship to the walkway -the level of dirt will be below the level of the walkway, so even if I graded, water would just pool up to the lip of the walkway then overflow from there. I think this is what the problem has always been. Obviously the drain is supposed to alleviate that except for the fact that it's limited on how deep it can go due to the chimney footing. Right now this is the most problematic area of the yard. The contractor who did our weep screed said that technically we can get closer to the weep screed because he waterproofed the siding under it and also added metal flashing as an additional layer of protection so even if water does pool up there it's not getting in the house easily. As long as it's somewhat graded to the point that water or dirt isn't going to cover the weep screed again (which was the original problem - previous owner covered the weep screed completely) it won't be a problem. Now, whether this would be to code or not I'm not sure. Since we're not planning on selling anytime soon (afaik haha) maybe we should take him at his word and ignore the code in this case.

Anyway, if we poured concrete here, we would still grade and slope it the similarly to how we would grade dirt. It's just that the cement would fill all the way to the same level as the existing walkway, which does have *some* grade to it. The thought is that, as long as the slab is sloped/graded away from the house and at the same level as the other walkway, the water will actually flow downhill and we can catch it with a drain/french drain/dry river bed/swale or whatever else on the *other* side of the walkway. But yes, I'd still be concerned with losing the flexibility of being able to run irrigation lines through this area in the future (not that I'd want to plant anything that needs irrigation here but more to provision for the backyard or whatever and being able to repair/replace anything that breaks)

Thanks for the more detailed explanation. I think that makes a lot more sense to me now and I understand your dilemma. I really don't like having dirt, gravel or anything up next to house siding and try to have at least six inches of space. It sounds like you have the grade available if it weren't for the sidewalk that is poured too high. To do the French drain between the sidewalk and the house, you would still have to at least tear up a section or two of your sidewalk, or bore underneath, for your French drain to gravity drain to daylight and to do both sections, on either side of the chimney.  I also don't like concrete up next to a house. Even if sloped, it can splash water from a hard rain up quite a ways onto your stucco siding. Also depending on slopes, a hard rain can still backwash into the joint between the concrete and the house before adequate draining toward the sidewalk, especially if you would have to put in a really shallow slope to keep maximum distance from the weep screed.

As long as the sidewalk is below the top of your house slab level and below the weep screed level, this is what I would do. Dig the dirt in the area between the sidewalk and the house down about six inches below the proper clearance of the weep screed (10 to 12 inches in your case), put in water permeable landscape fabric and six inches of landscaping rocks so you still have your 4 to 6" clearance. Don't bother with the French drain at all. Any water collected there by rainfall, will essentially be contained in a reservoir between the surface of the dirt and top surface of the gravel until it can be absorbed by the soil below. (I'm assuming your soil can absorb water fairly well.) The gravel keeps it from ponding or allowing mosquitoes and such from laying eggs. It shouldn't affect your foundation since you have a slab and I'm assuming you have rain gutters above that direct water into downspouts on the far side of the sidewalk. This allows you access to it in the future if needed and it probably the most reasonable option money wise as well.  This is essentially a slow version of a French drain since you are counting on absorption instead of a pipe to remove the water and would be able to still work above and around your chimney footing. With your fairly dry climate, it should be more than adequate.

The other more expensive option would be to just have someone come in and take out the sidewalk so the entire areas can be graded properly with the proper clearances and put in some combination of concrete and pavers sloped the proper way and end up with a step where your sidewalk goes through the gate.

The downspouts are roughly where I've dropped the arrows pointing down:


Your suggestion of using landscaping fabric + rocks is more or less a "pipeless" french drain I think. Except, I don't think you were suggesting to trench it but rather just naturally grade it. I wonder if it would make sense to still grade away from the home AND dig a trench next to the sidewalk to still have a french drain (but pipeless) directing run-off towards the catch basin. I think I saw a couple Youtube videos of people even using poly sheeting to help redirect water away but in this case, I think we want a combination of both absorption and allowing water to run-off.

So you're suggesting to lay landscaping fabric on the entire area practically from the wall of the house extended over to the walkway? Is this more so to prevent erosion as well as weeds? I heard that if you have enough rocks (a 3" or more layer) you won't have issues with weeds.

Oh, regarding the downspouts too, I think we may end up leveraging at least one or two rain barrels/cisterns to capture any water from the roof when it rains. Otherwise, I might want to create a rain garden of sorts in the front area around the catch basin. Perhaps a smaller scale rain garden (with plants that can absorb moisture but are still drought tolerant) would be OK against the house - maybe lavender, sage, fescue, etc?

You need to hire a true professional, Odell Complete Concrete. He's the friggin rockstar of concrete.
Thanks for the referral. We will definitely need to address the concrete alley on the other side of our property that pools water in various places. We'll need a contractor to break all that up, regrade, and install proper drainage there. We may tackle that closer to when we're ready to replace the HVAC/furnace systems.
« Last Edit: January 18, 2022, 09:35:19 AM by jeromedawg »

lthenderson

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Re: Concrete pour - abandon irrigation or remove?
« Reply #13 on: January 18, 2022, 03:53:56 PM »
Your suggestion of using landscaping fabric + rocks is more or less a "pipeless" french drain I think. Except, I don't think you were suggesting to trench it but rather just naturally grade it. I wonder if it would make sense to still grade away from the home AND dig a trench next to the sidewalk to still have a french drain (but pipeless) directing run-off towards the catch basin. I think I saw a couple Youtube videos of people even using poly sheeting to help redirect water away but in this case, I think we want a combination of both absorption and allowing water to run-off.

So you're suggesting to lay landscaping fabric on the entire area practically from the wall of the house extended over to the walkway? Is this more so to prevent erosion as well as weeds? I heard that if you have enough rocks (a 3" or more layer) you won't have issues with weeds.

Since you are on a slab, I don't think grading is really a necessity though I wouldn't want water getting underneath the slab.  But then again, I'm not familiar with California building standards and someone local might have a better opinion than I do. I would probably just slightly grade it just so the water in the pipeless French drain is as far away from the slab as possible. In my mind, I was just envisioning a water reservoir of sorts in the gravel until it is absorbed and not routing it to a catch basin which might also be a way to tackle this though would probably require repairs to your sidewalk to achieve.

The purpose of the landscape fabric in this case is to create a barrier between dirt and the rocks so they don't mingle over time and with water. The rock is essentially a giant filter and when it gets plugged up with dirt and debris, either from the top or below, it would lose effectiveness as a reservoir or to move water towards your catch basin. The landscape fabric does stop weeds when using lesser depths of gravel though if you were to put in six inches of gravel, this is probably not a concern.

jeromedawg

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Re: Concrete pour - abandon irrigation or remove?
« Reply #14 on: January 24, 2022, 10:41:47 AM »
Your suggestion of using landscaping fabric + rocks is more or less a "pipeless" french drain I think. Except, I don't think you were suggesting to trench it but rather just naturally grade it. I wonder if it would make sense to still grade away from the home AND dig a trench next to the sidewalk to still have a french drain (but pipeless) directing run-off towards the catch basin. I think I saw a couple Youtube videos of people even using poly sheeting to help redirect water away but in this case, I think we want a combination of both absorption and allowing water to run-off.

So you're suggesting to lay landscaping fabric on the entire area practically from the wall of the house extended over to the walkway? Is this more so to prevent erosion as well as weeds? I heard that if you have enough rocks (a 3" or more layer) you won't have issues with weeds.

Since you are on a slab, I don't think grading is really a necessity though I wouldn't want water getting underneath the slab.  But then again, I'm not familiar with California building standards and someone local might have a better opinion than I do. I would probably just slightly grade it just so the water in the pipeless French drain is as far away from the slab as possible. In my mind, I was just envisioning a water reservoir of sorts in the gravel until it is absorbed and not routing it to a catch basin which might also be a way to tackle this though would probably require repairs to your sidewalk to achieve.

The purpose of the landscape fabric in this case is to create a barrier between dirt and the rocks so they don't mingle over time and with water. The rock is essentially a giant filter and when it gets plugged up with dirt and debris, either from the top or below, it would lose effectiveness as a reservoir or to move water towards your catch basin. The landscape fabric does stop weeds when using lesser depths of gravel though if you were to put in six inches of gravel, this is probably not a concern.

We just had a professional landscaping company come out to assess and his suggestion veers away from the french drain - he was saying that it's nice in theory but in reality it probably wouldn't work well with the capacities we get during our "rain dumps" - he was going for the high flow large volume drainage solution which is to basically rip out the existing system, re-grade/re-pitch/re-slope, install a channel/trench drain in the backyard area and then replace the existing drainage in the side yard running to the catch basin. He wouldn't change anything about how the water is exiting to the catch basin currently other than adding a couple 90 degree elbows perhaps. But he was saying he would want to just install completely new drainage (and irrigation) in place of what we currently have just to ensure everything is working properly and we know exactly what is in place. He was suggesting replacing all irrigation lines while doing the drainage since everything will be dug up anyway. Total cost of everything, drainage + irrigation, ends up at just over $11k. I've had another couple landscapers (also licensed) quote me less than half the cost of this although the job perhaps may not have been quite as extensive. $11k seems quite high for something like this though - even if I updated the scope of the project with the prior landscapers, I still don't think they would quote as high as what this company has.

FWIW: the other landscapers I've had come look at everything all seem to be suggesting regular 3" PVC piping and area drains + catch basins. None of them have suggested french drains, dry river beds, etc... and if I ask any of them they say it's either "unnecessary" or "not effective" so I'm not sure what the turn-off is with french drains in my area. I forgot to mention that the *only* company touting a french drain solution was the professional drainage company who wanted have the french drain system up against the side of the home and implement the waterproof membrane in conjunction. It's very confusing trying to figure out what the best solution is for this since everyone has their own opinion about what works and what doesn't.

In theory, this doesn't seem to be that difficult of a project to DIY but practically I think it's harder than it is. Probably just being overwhelmed with the amount of dirt/soil/clay to trench and move around and just getting into the weeds with things. I think we'd really want at least 2-3 days that we could just dedicate to knocking this out if we really wanted to go the DIY route.
« Last Edit: January 24, 2022, 10:56:43 AM by jeromedawg »