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Discussion Starter · #1 ·
My backyard retains moisture along my fence line (75ft) about 4-5ft out. My yard slopes slightly towards the road in the right direction but an area outside my fence has very little slope, about 3” over 30ft span.

I seem to get runoff from my neighbors yard and downspouts as they are higher then me.

I was considering a French drain but not sure if the last 30ft outside my fence would be an issue with the minimal slope. The French drain would be dug shallow (maybe 2” of gravel on top) on the end just before it went to solid pipe to carry the water the last 30ft to the street.

I was trying to avoid a sump pump if possible just to keep things simple.

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Discussion Starter · #3 ·
So the area where your pic shows the string line is 3" over 30'?

That is a tough one. Where is the fence located, w.r.t. the property line?
The area with the string is the final 30ft with about a 3” slope to the top of the curb.

I own out to the roadway, my back fence Is right on my back property line.
 

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My backyard retains moisture along my fence line (75ft) about 4-5ft out. My yard slopes slightly towards the road in the right direction but an area outside my fence has very little slope, about 3” over 30ft span.
You only need one inch of slope every 10 feet. And, really, if no debris gets in there, such as by wrapping the french drain in fabric and not using any surface grates, you don't even need that. And normally I'd say corrugated pipe is just fine most of the time, but the less slope there is, the better using PVC instead would be.

Though, again, if debris isn't getting in there, then the corrugated ribs aren't a debris problem. Though they would hold some water and nearby trees could sniff out the water and potentially create more root problems. Potentially.

I assume you plan on drilling through the curb for the discharge outlet. If not, maybe you could skip the last segment to the curb and instead have the drain outlet discharge near the fence and then run on the surface to the curb. There might be an erosion problem then doing that in the ground's current state since there's no grass there. I don't know how easy it would be to grow grass in that area. Just tossing out the idea quick.
 

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Discussion Starter · #5 ·
You only need one inch of slope every 10 feet. And, really, if no debris gets in there, such as by wrapping the french drain in fabric and not using any surface grates, you don't even need that. And normally I'd say corrugated pipe is just fine most of the time, but the less slope there is, the better using PVC instead would be.

Though, again, if debris isn't getting in there, then the corrugated ribs aren't a debris problem. Though they would hold some water and nearby trees could sniff out the water and potentially create more root problems. Potentially.

I assume you plan on drilling through the curb for the discharge outlet. If not, maybe you could skip the last segment to the curb and instead have the drain outlet discharge near the fence and then run on the surface to the curb. There might be an erosion problem then doing that in the ground's current state since there's no grass there. I don't know how easy it would be to grow grass in that area. Just tossing out the idea quick.
Thanks for the PVC suggestion, I was thinking of using the SCH40 over the cheaper stuff at the big box stores unless the thinner big box stuff would be fine. I’m in Central Virginia so we do have freezes but not terribly long.

The area with the string isn’t level (small dips), if I discharged the water at the fence I may need to level the area first. I just cleared out a few years of leaves from the area which is why it’s bare dirt now. The leaves weren’t helping the drainage situation.

I checked with the County and highway department, they said absolutely I can’t modify the curb. That’s what I get for trying to do it right. If I could have just cut a core out of the curb I would have gained more slope.

I was debating brining the solid discharge pipe about 5ft short of the curb and recessing an area of gravel into the ground to act like a dry creek bed essentially to carry the water to the street. Not sure if this is a good idea?

Lastly, would the French drain work decent having 2-3” of gravel under the perforated pipe with 2” of gravel on top, wrapped in a “burrito” with non-woven filter fabric. On the uphill side I would be able to have more gravel if needed. I was thinking the trench to be made 12-14” wide?
 

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If I could have just cut a core out of the curb I would have gained more slope.
It doesn't sound or look like you are able to daylight a french drain, and there isn't a huge water problem, so no reason to do one. The strict rule about the curb cut is the norm in neighborhoods, rules like that is what keeps your house value up. Otherwise, people would be running all kinds of things out to the street and the curb would be swiss cheese.

It seems like the grading is working - both your and his water is running to the back shared prop line. Just a little too much water from him maybe. The tree floor outside the fence looks a bit high and filthy that might be impeding the quickness of the water draining towards the street. What I would do is put a small berm along the entire fence line to stop most of the neighbor's water. Then clean out a 4'-5' area between curb and fence and lay sod (crossing both his and your side of the fence), if necessary just putting a very shallow dip of a bowl to collect water if you feel you want to steepen the swale's slope within your yard.
 

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Discussion Starter · #7 ·
The photo with the bare dirt isn’t where my water problem is, that’s where I want to discharge it to for it to find it’s way to the street. My problem area is inside my fence, I’m unable to walk in a 75ft x 4ft strip against my fence for about 5 months a year.
 

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I am completely aware of the problem. The water is trying to drain towards the street. You need to allow it to get there. You feel the slope parallel to the back fence is not steep enough. The gruff on the ground outside the fence can impede the sheetflow of water (water running on top the saturated ground). The water from your yard has to pass through the side fence and trees to get to the street (well, backside of curb) no? Clean up a little area. You said you owned to the street (don't know how, but you are still responsible for that parkway upkeep even if your side prop line falls short).

The "dip of a bowl" I talked about, think about water seeking level. If it's draining a certain direction, and there is a low spot, it will "hurry up" to get to that low spot. And, if the ground is saturated and you have too much water, this will give a little detention area outside your yard for some reprieve. Described as a "bowl" rather than a ditch or hole as a bowl would not be so noticeable when it is dry (like a few inches deep in center). And if you decide to regrade the 3" in 30' parallel to the back fence to a steeper slope, a "bowl" will be lower and will allow that steeper slope instead of having to go up a hill at the side fence.

The small berm will help you stop the neighbors sheetflow. It's no more than landscaping. Talking like 6"-10" high gradual slope.
 

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I was debating brining the solid discharge pipe about 5ft short of the curb and recessing an area of gravel into the ground to act like a dry creek bed essentially to carry the water to the street. Not sure if this is a good idea?

Lastly, would the French drain work decent having 2-3” of gravel under the perforated pipe with 2” of gravel on top, wrapped in a “burrito” with non-woven filter fabric. On the uphill side I would be able to have more gravel if needed. I was thinking the trench to be made 12-14” wide?
Your 5ft short idea is similar to when I said maybe consider having the discharge outlet way up by the fence. No reason to stop 5ft from the curb if you can stop 30 ft from the curb. But maybe stopping near the fence is more difficult. Hard to tell these things with just a couple pictures and not actually being there.

Regardless of 5ft from the curb or 30ft, yeah, dry creek bed type of thing so the water flows on the surface from that point. I said grass before since it hides everything better, but if doing a dry creek bed it could be a feature of the yard and draw attention to it on purpose. Hey, neighbors and passing vehicles, look at how pretty my dry creek bed is.

Or something similar like a path of two bricks/pavers butted together forming a V for water to flow on. Or just a flat trough of some kind made out of concrete or plastic or whatever. Just tossing out surface flow ideas.

2-3" of pipe gravel is fine, especially if wrapped. Just need to keep the soil (and wrap fabric) from being right against the pipe, really.

I was typing fast earlier and didn't consider the full situation like 3onthetree mentioned. I was thinking you had more of a subsurface water problem. If you're mainly trying to stop surface water from your neighbor, then maybe a swale/berm would be enough. With grass growing on it, it might be invisible, but even if it's a bit obvious, it'd be less obvious than having a line of surface gravel across the lawn.
 

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Discussion Starter · #11 ·
Your 5ft short idea is similar to when I said maybe consider having the discharge outlet way up by the fence. No reason to stop 5ft from the curb if you can stop 30 ft from the curb. But maybe stopping near the fence is more difficult. Hard to tell these things with just a couple pictures and not actually being there.

Regardless of 5ft from the curb or 30ft, yeah, dry creek bed type of thing so the water flows on the surface from that point. I said grass before since it hides everything better, but if doing a dry creek bed it could be a feature of the yard and draw attention to it on purpose. Hey, neighbors and passing vehicles, look at how pretty my dry creek bed is.

Or something similar like a path of two bricks/pavers butted together forming a V for water to flow on. Or just a flat trough of some kind made out of concrete or plastic or whatever. Just tossing out surface flow ideas.

2-3" of pipe gravel is fine, especially if wrapped. Just need to keep the soil (and wrap fabric) from being right against the pipe, really.

I was typing fast earlier and didn't consider the full situation like 3onthetree mentioned. I was thinking you had more of a subsurface water problem. If you're mainly trying to stop surface water from your neighbor, then maybe a swale/berm would be enough. With grass growing on it, it might be invisible, but even if it's a bit obvious, it'd be less obvious than having a line of surface gravel across the lawn.
Thanks for the suggestions. My main concern with stopping the pipe once it clears my fence line is to no cause more of an issue with my neighbor behind me as he has a worse situation.

On my fence that runs parallel to the road it seems the problem is both surface and subsurface which I believe is from a small dip in that area. I replaced a fence post in that area recently and the water was right to the top of the hole, I dug around 30” down.

On The opposite side of my yard but still close to my back fence line which is the problem area the problem is surface water. I dug a shovel deep the other day and the 4-5” of topsoil was completely saturated. The clay under was fairly dry. I’m sure this is due to going up in elevation?
 

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Discussion Starter · #12 ·
Jmunk, what route does the water from your downspouts take to get to the street/stormdrain?
Attached is a photo, my house has the yellow circle on it. The red arrows are gutters, my neighbor has two aimed that slope down towards my yard which don’t help the issue.
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I plan to connect the two on the back of the house to solid PVC and carry past the fence where it slopes down. I also debated adding a short section of French drain to the beginning of the run to try and catch the surface water from my neighbors two gutters that he has aimed towards me.

I’m not sure how much the gutter discharge contribute to the problem but nonetheless it’s not helping.
 

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Discussion Starter · #13 ·
I am completely aware of the problem. The water is trying to drain towards the street. You need to allow it to get there. You feel the slope parallel to the back fence is not steep enough. The gruff on the ground outside the fence can impede the sheetflow of water (water running on top the saturated ground). The water from your yard has to pass through the side fence and trees to get to the street (well, backside of curb) no? Clean up a little area. You said you owned to the street (don't know how, but you are still responsible for that parkway upkeep even if your side prop line falls short).

The "dip of a bowl" I talked about, think about water seeking level. If it's draining a certain direction, and there is a low spot, it will "hurry up" to get to that low spot. And, if the ground is saturated and you have too much water, this will give a little detention area outside your yard for some reprieve. Described as a "bowl" rather than a ditch or hole as a bowl would not be so noticeable when it is dry (like a few inches deep in center). And if you decide to regrade the 3" in 30' parallel to the back fence to a steeper slope, a "bowl" will be lower and will allow that steeper slope instead of having to go up a hill at the side fence.

The small berm will help you stop the neighbors sheetflow. It's no more than landscaping. Talking like 6"-10" high gradual slope.
Good points.

Is it safe to say once the lower ground is saturated the water ground saturation area to grows up hill? I have debated in the past covering the soggy area (75’x4’) with river rock but that’s more masking the problem then resolving it.
 

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Can't just make a swale/berm near your property line between you and your side neighbor to make his gutter water he's dumping at you then flow to the front street?
 

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^^ That's what I was thinking about. Depends how much fall there is there. Seems like the 3" in 30' is on the street side, though, not the next door neighbor side. OP, do you have any drop on the side with the neighbor?

Worst case, maybe you can get by with a dry well in the back yard.

What kind of soil do you have? Go to the USDA web soil survey and see what's in your area.
 

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Discussion Starter · #16 · (Edited)
^^ That's what I was thinking about. Depends how much fall there is there. Seems like the 3" in 30' is on the street side, though, not the next door neighbor side. OP, do you have any drop on the side with the neighbor?

Worst case, maybe you can get by with a dry well in the back yard.

What kind of soil do you have? Go to the USDA web soil survey and see what's in your area.
Your correct the 3” drop is on the street side. Have a consistent grade with the side neighbor. I get some water from him but the neighbor behind me has a bigger water problem at our shared fence then I do.

I did have a contractor come by today to look at it. He suggested a French drain with a sump. I’m not wild about a sump pump system. He did also mention a dry well, but wasn’t sure how well the water would percolate out and if it would fill up and cause the same issue. I’m not sure how well this clay soil drains once you get deep.

Here is a photo of a problem area on my street side. The ground flattens out here and there is a bowl shape. I know filling in the bowl will help inside the fence but I’m not sure where it will push the water.

Plant Tire Water Wood Truck
 

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The yard puddle bowl may be a good thing as-is. The question is how much digging under the fence area would it take to get the yard puddle bowl to start flowing to the other side of the fence.

If you have to dig deep, that's when a dry creek bed would come in handy, since when it's filled with rocks it will look normal no matter how deep it's been dug.

And then the question is what would it take to get the rest of the inside back fence water to the yard puddle bowl area.
 

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He's only got 3" down to the TC on that side. Not a lot of room to dig for positive surface drainage.

@Jmunk do you own the area outside the fence, or is that public ROW?

One (probably fairly expensive) solution would be to raise the entire back yard to drain:
Screenshot Terrestrial plant Font Soil Pc game

If you raise your back yard you keep your neighbors' water on their side of the fence.
 

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Discussion Starter · #19 ·
The yard puddle bowl may be a good thing as-is. The question is how much digging under the fence area would it take to get the yard puddle bowl to start flowing to the other side of the fence.

If you have to dig deep, that's when a dry creek bed would come in handy, since when it's filled with rocks it will look normal no matter how deep it's been dug.

And then the question is what would it take to get the rest of the inside back fence water to the yard puddle bowl area.
A week or so ago I did do a test near the puddle on the outside of the fence, I dug a short trench about 3” deep and water flowed until the trench filled up. I think if I dug the trench a few inches deeper and longer towards the street it would flow more water until I ran out of slope. I see what your saying about a dry creek bed. That would shift the wet area perhaps outside my yard to the wooded area, anything is a help.

If I cut a shallow swale along my back fence line it may help in “channeling” the water where I wanted it to go, until I ran out of slope which is my biggest issue.

I need to setup a sting line along the entire length and get the slope measurements.
 

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Discussion Starter · #20 ·
He's only got 3" down to the TC on that side. Not a lot of room to dig for positive surface drainage.

@Jmunk do you own the area outside the fence, or is that public ROW?

One (probably fairly expensive) solution would be to raise the entire back yard to drain:
View attachment 681245
If you raise your back yard you keep your neighbors' water on their side of the fence.
Maybe I’m missing it, what are the numbers relative to?

I’m trying to be a nice neighbor and not build my yard up and push the water back over. I guess that’s the right thing to do?

I own the wooded area, so I own about 25ft from the side fence line to the street and about the last 5ft isn’t mine, I wouldn’t see anyone fussing over me doing anything any improvements.
 
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