Yard Drainage Question

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LifeIsGood
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Yard Drainage Question

Post by LifeIsGood »

The area between my house and my neighbor’s has started to develop a slight ”ravine” where water washes and drains. There is an 8’ 6” drop over 50 feet as water works its way to the storm water inlet. All the water flowing down this channel is coming from our ~ 1/8 acre back yards and sources other than roofs and gutters which drain via 4” corrugated pipe. I know there’s much more missing in order to provide advice but I’m just looking for a “back of the envelope” calculation.
Here’s the 3 options I have come up with:

1- Bury another 4” corrugated pipe with 2 or 3 9”x12” catch basin inlets and dump into the storm water inlet.
2- Lay a bed of river stone in the depression. Topography will make it difficult to get stone to this location.
3- Plant hearty fast growing plants such as Lirope or mondo grass.

I’d love to hear what you think.
jebmke
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Re: Yard Drainage Question

Post by jebmke »

My first approach in situations like this is native plants of some sort. Could be grass or something else. Have also used Vinca in a couple of areas.
Don't trust me, look it up. https://www.irs.gov/forms-instructions-and-publications
Glockenspiel
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Re: Yard Drainage Question

Post by Glockenspiel »

Bury a perforated 4" or 6" diameter french drain in a trench surrounded with 3/4" graded angular rock, with the small plastic catch basin inlets at the ravine bottom, and dump the water into the storm inlet in the roadway. Use a geotextile fabric around the bottom and sides of the rock trench to keep the surrounding soil from mixing with the rock.

This will do a great job of keeping that ravine more dry.
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LifeIsGood
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Re: Yard Drainage Question

Post by LifeIsGood »

Curious why you suggested putting the catch basin inlets at the bottom. Wouldn't further erosion have occurred by the time the water got to the bottom?
Glockenspiel wrote: Wed Mar 15, 2023 3:14 pm Bury a perforated 4" or 6" diameter french drain in a trench surrounded with 3/4" graded angular rock, with the small plastic catch basin inlets at the ravine bottom, and dump the water into the storm inlet in the roadway. Use a geotextile fabric around the bottom and sides of the rock trench to keep the surrounding soil from mixing with the rock.

This will do a great job of keeping that ravine more dry.
Mr. Rumples
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Re: Yard Drainage Question

Post by Mr. Rumples »

Your state/county extension office is a start to find out about drainage and a "rain" garden. By way of example in GA: https://www.cobbcounty.org/water/educat ... in-gardens
https://www.walterreeves.com/landscapin ... designing/

If the storm water outlet is owned by the locality, they might come out and remedy it or make suggestions. Slowing the water down might be an option by placing landscaping timbers to create a sort of terrace, allowing more areas to be soaked.

My property is over hardpan. To increase water going into the soil, I literally had to break it up with a drill and a 18" masonry bit. The local extension agent will have an idea if hardpan is an issue. Hardpan can exist in wooded areas, the Piedmont Hardpan Forest runs from VA to GA. https://www.dcr.virginia.gov/natural-he ... an-forests
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tunafish
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Re: Yard Drainage Question

Post by tunafish »

A picture would be useful. Also I am confused by slight vs 8 foot drop.

What is the concern? It sounds like you have a ready made swale.
Glockenspiel
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Re: Yard Drainage Question

Post by Glockenspiel »

LifeIsGood wrote: Thu Mar 16, 2023 4:44 am Curious why you suggested putting the catch basin inlets at the bottom. Wouldn't further erosion have occurred by the time the water got to the bottom?
Glockenspiel wrote: Wed Mar 15, 2023 3:14 pm Bury a perforated 4" or 6" diameter french drain in a trench surrounded with 3/4" graded angular rock, with the small plastic catch basin inlets at the ravine bottom, and dump the water into the storm inlet in the roadway. Use a geotextile fabric around the bottom and sides of the rock trench to keep the surrounding soil from mixing with the rock.

This will do a great job of keeping that ravine more dry.
I meant at the low point of the V, in the ravine, if you're looking at it in a cross-sectional view. You could space the catch basins 30-100 feet apart, depending on how long the ravine runs.
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LifeIsGood
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Re: Yard Drainage Question

Post by LifeIsGood »

Thanks everyone for your feedback and suggestions.
A couple of clarifications: the "ravine" (note quotes) is just an area of erosion a few inches deep where water has started to form a channel. I'd like to prevent this from getting much deeper or wider.
The idea of a Rain Garden is appealing and Walter Reeve's site certainly has a detailed write up on this. They also advise NOT putting one in an area that has a slope greater than 12% and mine is about 18% so concerns me a bit.
Terracing is an interesting idea I hadn't considered.
Mr. Rumples
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Re: Yard Drainage Question

Post by Mr. Rumples »

Your extension agent might be able to make suggestions. For my yard, I have slowed the water by placing fallen limbs up to 3" in diameter down. I'm the crazy old man asking folks if I can have their fallen limbs after a storm. The downside the south is that one has to wear leather gloves to ensure not getting bitten by a Black Widow spider and keep eyes peeled for snakes; the landscape timber would work. There are numerous links to be found by googling "slowing water on hill." A French drain, a runnel, shrubs, berms, a rock drainage ditch, terrace, are the basic methods adjusted to the site. Here is a link with pictures of a slope: https://toolbox.coffeeandclimate.org/to ... er-runoff/ Even cinder blocks in an informal terrace would work to slow the water. Over time, they would get moss on them, softening the look.

To carry it to an extreme, a ha-ha wall can be installed: https://www.treehugger.com/what-is-ha-ha-5525880 A brick runnel at its base adds to directing the water flow.
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JimmyJoeMeeker
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Re: Yard Drainage Question

Post by JimmyJoeMeeker »

Consult the NDS website, http://www.ndspro.com which has a drainage calculator to help you quantify the volume of water causing the erosion. This helps to size the solution.

Comments about number and size of catch basins, french drains, and pipe(s) could prove to be correct, incorrect or overkill based on the calculation.

A rain garden will not solve erosion or moving water. It's to capture, store and percolate water that is collected at a low point.
Jack FFR1846
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Re: Yard Drainage Question

Post by Jack FFR1846 »

When we had our detached garage built, the builder noticed that in the middle of our driveway circle, water would collect from water coming down a hill and from our roof. Before completing the drainage around the garage, he put perforated pipe with landscape fabric from the circle into the garage drainage. Since doing that, we've never had water build up in there despite having put in a sump pump in the house with an exit into that circle.

With as much of a slope as you have, I would do that and then top the pipe with crushed stone to prevent erosion. Even with the pipe, that steep of a hill could easily form big erosion pits during heavy rain. Perhaps even plant ground cover on each side of the stone to further prevent erosion.
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HomeStretch
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Re: Yard Drainage Question

Post by HomeStretch »

LifeIsGood wrote: Fri Mar 17, 2023 4:51 am … A couple of clarifications: the "ravine" (note quotes) is just an area of erosion a few inches deep where water has started to form a channel. I'd like to prevent this from getting much deeper or wider. …
Catch drains/basins and pipes work but you have to remember to keep them clean of leaves and debris. Also water can change paths a bit over time which involves resetting the drains.

Have you consider a swale if you have room between the two properties? Search the internet for info/pictures. It would involve widening and deepening the path that the water has created in order to channel the water from the back of your property to the storm water inlet located at the front of your property. You can landscape on the sides of the swale and add large decorative rocks to the bottom to create a landscape feature.
homebuyer6426
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Re: Yard Drainage Question

Post by homebuyer6426 »

LifeIsGood wrote: Wed Mar 15, 2023 2:58 pm The area between my house and my neighbor’s has started to develop a slight ”ravine” where water washes and drains. There is an 8’ 6” drop over 50 feet as water works its way to the storm water inlet. All the water flowing down this channel is coming from our ~ 1/8 acre back yards and sources other than roofs and gutters which drain via 4” corrugated pipe. I know there’s much more missing in order to provide advice but I’m just looking for a “back of the envelope” calculation.
Here’s the 3 options I have come up with:

1- Bury another 4” corrugated pipe with 2 or 3 9”x12” catch basin inlets and dump into the storm water inlet.
2- Lay a bed of river stone in the depression. Topography will make it difficult to get stone to this location.
3- Plant hearty fast growing plants such as Lirope or mondo grass.

I’d love to hear what you think.
Check out the Youtube channel Gate City Foundation Drainage if you want to dive deep into this.

1. Schedule 40 PVC pipe works better because it's smooth walled and doesn't get clogged up easily. It can handle shallower grades than corrugated. You may want to check if your current corrugated pipe is blocked.
2. Don't use round stones for drainage. You can use them as a top layer to cover something else, but underneath it should be angular stone. Consider that any sort of raised rocks may create a lawnmowing/weed problem.
3. Are these plants intended to cover up the standing water, or to absorb it? If you hope to absorb it, you may be better off with small trees/large bushes. Go for varieties which tend to live near rivers or wet ground. Some types of willow, poplar, birch, maple would work. Don't use trees if you're putting a pipe there though, the roots will find their way in.
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checkman414
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Re: Yard Drainage Question

Post by checkman414 »

Cobb County was a random example @Mr Rimples? That's where I live. Pic would help, there are lots of options
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Sandtrap
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Re: Yard Drainage Question

Post by Sandtrap »

LifeIsGood wrote: Wed Mar 15, 2023 2:58 pm The area between my house and my neighbor’s has started to develop a slight ”ravine” where water washes and drains. There is an 8’ 6” drop over 50 feet as water works its way to the storm water inlet. All the water flowing down this channel is coming from our ~ 1/8 acre back yards and sources other than roofs and gutters which drain via 4” corrugated pipe. I know there’s much more missing in order to provide advice but I’m just looking for a “back of the envelope” calculation.
Here’s the 3 options I have come up with:

1- Bury another 4” corrugated pipe with 2 or 3 9”x12” catch basin inlets and dump into the storm water inlet.
2- Lay a bed of river stone in the depression. Topography will make it difficult to get stone to this location.
3- Plant hearty fast growing plants such as Lirope or mondo grass.

I’d love to hear what you think.
To OP:
Notes and questions and things:

**Questions for you***

1.
Is this a total "fall" of 8 feet . . 6 inches. . over a "run" of . . . 50 feet?
2
What "storm water inlet". . ?
Is this a street drain by the front sidewalk in front of the home?
3
you and your neighbor "each" have 1/8 of an acre of water, plus roof gutter drains. . (for 2 homes). . draining "all" of that water into the area between the homes that you are talking about?
4
Do you now have a deep rut eroded into the soil in the area you are talking about?
5
What drainage measures are there now?
Is it plugged up?
Is it the black 4 inch flexible corrugated drain lines that's typical installed below ground with several grill drains at the surface or is this perforated and depends on soil drainage to fill? (never lasts for long nor works as intended, usually, it depends). So, what' do you have now?
6
A picture or sketch would really help as well as better data.
You can edit your original post using the pencil icon to add this.
Otherwise, suggestions are all over the place and not specific to what you have. . and what others have done may and usually doesn't apply to your exact situation.

I hope this is helpful for you.
j

(insert standard dis laimer for opinionizations and onions and experiences and perspectives, this is only one).
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Topic Author
LifeIsGood
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Re: Yard Drainage Question

Post by LifeIsGood »

View looking uphill

Image

Looking downhill with gutter drain and storm water inlet at bottom


Image
Sandtrap wrote: Fri Mar 17, 2023 8:32 am
LifeIsGood wrote: Wed Mar 15, 2023 2:58 pm The area between my house and my neighbor’s has started to develop a slight ”ravine” where water washes and drains. There is an 8’ 6” drop over 50 feet as water works its way to the storm water inlet. All the water flowing down this channel is coming from our ~ 1/8 acre back yards and sources other than roofs and gutters which drain via 4” corrugated pipe. I know there’s much more missing in order to provide advice but I’m just looking for a “back of the envelope” calculation.
Here’s the 3 options I have come up with:

1- Bury another 4” corrugated pipe with 2 or 3 9”x12” catch basin inlets and dump into the storm water inlet.
2- Lay a bed of river stone in the depression. Topography will make it difficult to get stone to this location.
3- Plant hearty fast growing plants such as Lirope or mondo grass.

I’d love to hear what you think.
To OP:
Notes and questions and things:

**Questions for you***

1.
Is this a total "fall" of 8 feet . . 6 inches. . over a "run" of . . . 50 feet?
From the top of the "hill" to the bottom, the fall is 8' 6"
2
What "storm water inlet". . ?
Is this a street drain by the front sidewalk in front of the home?
The storm water inlet is the grate shown at the bottom of the image looking downhill. It's the lowest point on the property - it's below the lowest point of my house and below street level.
3
you and your neighbor "each" have 1/8 of an acre of water, plus roof gutter drains. . (for 2 homes). . draining "all" of that water into the area between the homes that you are talking about?
Not sure exactly what you are asking
4
Do you now have a deep rut eroded into the soil in the area you are talking about?
The rut is shown on both pics. I don't think I'd call it "deep" but that is subjective
5
What drainage measures are there now?
Is it plugged up?
Is it the black 4 inch flexible corrugated drain lines that's typical installed below ground with several grill drains at the surface or is this perforated and depends on soil drainage to fill? (never lasts for long nor works as intended, usually, it depends). So, what' do you have now?
The only drain installed currently is the black 4 inch flexible corrugated pipe shown in the pic. It takes water from the gutters/downspouts on that side of the house and dumps it into the storm inlet. I have verified that it is open and draining.
6
A picture or sketch would really help as well as better data.
You can edit your original post using the pencil icon to add this.
Otherwise, suggestions are all over the place and not specific to what you have. . and what others have done may and usually doesn't apply to your exact situation.

I hope this is helpful for you.
j

(insert standard dis laimer for opinionizations and onions and experiences and perspectives, this is only one).
jebmke
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Re: Yard Drainage Question

Post by jebmke »

looking at the photos and ignoring cost for the time being, my inclination would be to have a terraced fall that absorbed any eroded soil and other bad stuff before dumping water into the storm drain. But I live in an area where such mitigation measures are required in some cases and heavily encouraged in other cases in order to avoid dumping contaminated water into the watershed.
Don't trust me, look it up. https://www.irs.gov/forms-instructions-and-publications
Mr. Rumples
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Re: Yard Drainage Question

Post by Mr. Rumples »

Due to the proximity to the house, the slope and the climate, I would put in a cinder block or concrete block terrace and fill it with stone. It would be a one time expense; while concrete blocks would require a base, cinder blocks are more forgiving if one wants an unfinished look - though technically they would need one. Instead of stones, the fill could be compost/dirt/leaves with plants. Liriope would work since their roots are strong, store water, and they thrive on neglect, but there are most likely native plants which would work. The problem with plants is even the ones which thrive on neglect will need some maintenance and they might provide a home for mice or other critters. Decking 4x4's would also work since they are treated for insects.

I know stone was mentioned as being difficult to get to the spot, but with labor it can be dumped via a wheelbarrow. This is something a landscape company might take on. I had a septic tank collapse and they had to fill that void with stone - an entire dump truck load had to hauled via wheelbarrows to the side of the house - trees blocked truck access.
Last edited by Mr. Rumples on Sun Mar 19, 2023 11:46 am, edited 1 time in total.
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checkman414
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Re: Yard Drainage Question

Post by checkman414 »

I would add small drain at the top and connect underground with small corrugated pipe, that would hit most the issue at the source. Would also fill with stone along where it has errored. Very small amount of money to do both. Cheers
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Sandtrap
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Re: Yard Drainage Question

Post by Sandtrap »

To OP:
Thanks so much for posting the pictures. It explains everything.
Some notes and questions:
1
Is there an upper drainage culvert with grill that drains underground to that black corrugated pipe that is shown emptying into the lower culvert grate?
Or. . . Is there no upper drainage culvert and the black pipe shown is a perforated (uselesss) pipe burried at the low point below the drainage "erroded" swale water cut now?
2
This is a lot of slope and there's no time for the water to soak into the ground, so perforated pipe and "french drain" style measures are not effective in a heavy downpour.
3
Goals:
a) get the water out of the area asap on heavy downpours so it doesn't soak the home foundations on either side.
b) underground, channel the water through 4 inch "solid" (not perforated, not corrugated) ABS/PVC drain pipe systems that take the house gutter drain lines directly to the drain down below.
c) take measures to completely stop the erosion that is happening between the homes by. .. .this:

Measures:
1. First install new smooth 4 inch drain lines per above, to channel all the home gutter downspouts.
2. Second, if possible and there is a flat area uphill, not shown on the photo's, and currently there indeed is an upper drainage culvert, then, install a smooth bore 4 inch solid drain pipe from that to empty downhill at the bottom. Bury the pipe.
3. After the below ground installs are done. Grade the area between the homes so it is smooth along both sides of the property line but with a shallow nice looking swale at the center.
4. Install "steps" along both sides of the property line using pavers, etc.
5. Install a non eroding lining in the center swale that is the steep part of the hill.
6. Install "Rip Rap" rock to cover the swale from the base of the hill to the top. Also on the flats above if that works. No Photo so verify.
a) Note: Rip Rap rock is a type of pattern of broken rock that makes them interlock, the opposite from smooth river rock. You might see it on commercial or city and county drain culverts in town, and on steep grade drainage swales. The rocks do not tumble in heavy water wash from hard rainfall.

Note: Do the above with the heaviest expected rainfall in mind. AKA: (100 year flood) is called in some counties. If you do that, then any lighter rainfall will all be a "non issue".

End Goals:
1. Complete peace of mind and the issue is solve and done with.
2. Everything is done tastefully to keep up the value of the property, looks great, and is a functional measure.
3. Do things once and once only. If things are done "Mickey Mouse" here and there to cut corners or save costs, etc, then it will come back with more water and erosion issues in the future.
4. With this type of steep slope and the water erosion shown, planting anything to be a cure or solve anything is futile.
5. If the heavy erosion cut is the property line, then maybe the neighbor can split costs with you?
6. Hire reputable licensed and insured contractors only. Get multiple bids. Be sure they are all bidding on the same work and products used.

I hope this is helpful for you.
j
(insert standard dislaimer for opinionizations and onions and so forth).
*I've hired subs many many times for this type of thing and every project is a little different in design to take care of the problem for good. We've also done many that were done poorly by DIY owners, etc, or other subs and turned into disasters after heavy storms. There are many ways to design something to solve your water drainage problem, this is just one or some options noted in the missive above.
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Topic Author
LifeIsGood
Posts: 1243
Joined: Mon Feb 11, 2008 7:43 pm
Location: Atlanta, GA

Re: Yard Drainage Question

Post by LifeIsGood »

Sandtrap, thanks so much for your suggestions. I'll proceed as you recommended. My neighbor has already offered to split the costs.
BTW, his downspouts also appear to be connected to 4" corrugated pipe but I can't find an outlet. That might be part of the problem and need to be addressed before starting.
Sandtrap wrote: Sun Mar 19, 2023 11:17 am To OP:
Thanks so much for posting the pictures. It explains everything.
Some notes and questions:
1
Is there an upper drainage culvert with grill that drains underground to that black corrugated pipe that is shown emptying into the lower culvert grate?
Or. . . Is there no upper drainage culvert and the black pipe shown is a perforated (uselesss) pipe burried at the low point below the drainage "erroded" swale water cut now?
The black corrugated pipe is only connected to 3 downspouts. That's the only inlet, It is NOT perforated.
2
This is a lot of slope and there's no time for the water to soak into the ground, so perforated pipe and "french drain" style measures are not effective in a heavy downpour.
3
Goals:
a) get the water out of the area asap on heavy downpours so it doesn't soak the home foundations on either side.
b) underground, channel the water through 4 inch "solid" (not perforated, not corrugated) ABS/PVC drain pipe systems that take the house gutter drain lines directly to the drain down below.
c) take measures to completely stop the erosion that is happening between the homes by. .. .this:

Measures:
1. First install new smooth 4 inch drain lines per above, to channel all the home gutter downspouts.
2. Second, if possible and there is a flat area uphill, not shown on the photo's, and currently there indeed is an upper drainage culvert, then, install a smooth bore 4 inch solid drain pipe from that to empty downhill at the bottom. Bury the pipe.
3. After the below ground installs are done. Grade the area between the homes so it is smooth along both sides of the property line but with a shallow nice looking swale at the center.
4. Install "steps" along both sides of the property line using pavers, etc.
5. Install a non eroding lining in the center swale that is the steep part of the hill.
6. Install "Rip Rap" rock to cover the swale from the base of the hill to the top. Also on the flats above if that works. No Photo so verify.
a) Note: Rip Rap rock is a type of pattern of broken rock that makes them interlock, the opposite from smooth river rock. You might see it on commercial or city and county drain culverts in town, and on steep grade drainage swales. The rocks do not tumble in heavy water wash from hard rainfall.

Note: Do the above with the heaviest expected rainfall in mind. AKA: (100 year flood) is called in some counties. If you do that, then any lighter rainfall will all be a "non issue".

End Goals:
1. Complete peace of mind and the issue is solve and done with.
2. Everything is done tastefully to keep up the value of the property, looks great, and is a functional measure.
3. Do things once and once only. If things are done "Mickey Mouse" here and there to cut corners or save costs, etc, then it will come back with more water and erosion issues in the future.
4. With this type of steep slope and the water erosion shown, planting anything to be a cure or solve anything is futile.
5. If the heavy erosion cut is the property line, then maybe the neighbor can split costs with you?
6. Hire reputable licensed and insured contractors only. Get multiple bids. Be sure they are all bidding on the same work and products used.

I hope this is helpful for you.
j
(insert standard dislaimer for opinionizations and onions and so forth).
*I've hired subs many many times for this type of thing and every project is a little different in design to take care of the problem for good. We've also done many that were done poorly by DIY owners, etc, or other subs and turned into disasters after heavy storms. There are many ways to design something to solve your water drainage problem, this is just one or some options noted in the missive above.
User avatar
Sandtrap
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Re: Yard Drainage Question

Post by Sandtrap »

LifeIsGood wrote: Mon Mar 20, 2023 5:45 am Sandtrap, thanks so much for your suggestions. I'll proceed as you recommended. My neighbor has already offered to split the costs.
BTW, his downspouts also appear to be connected to 4" corrugated pipe but I can't find an outlet. That might be part of the problem and need to be addressed before starting.
Sandtrap wrote: Sun Mar 19, 2023 11:17 am To OP:
Thanks so much for posting the pictures. It explains everything.
Some notes and questions:
1
Is there an upper drainage culvert with grill that drains underground to that black corrugated pipe that is shown emptying into the lower culvert grate?
Or. . . Is there no upper drainage culvert and the black pipe shown is a perforated (uselesss) pipe burried at the low point below the drainage "erroded" swale water cut now?
The black corrugated pipe is only connected to 3 downspouts. That's the only inlet, It is NOT perforated.
2
This is a lot of slope and there's no time for the water to soak into the ground, so perforated pipe and "french drain" style measures are not effective in a heavy downpour.
3
Goals:
a) get the water out of the area asap on heavy downpours so it doesn't soak the home foundations on either side.
b) underground, channel the water through 4 inch "solid" (not perforated, not corrugated) ABS/PVC drain pipe systems that take the house gutter drain lines directly to the drain down below.
c) take measures to completely stop the erosion that is happening between the homes by. .. .this:

Measures:
1. First install new smooth 4 inch drain lines per above, to channel all the home gutter downspouts.
2. Second, if possible and there is a flat area uphill, not shown on the photo's, and currently there indeed is an upper drainage culvert, then, install a smooth bore 4 inch solid drain pipe from that to empty downhill at the bottom. Bury the pipe.
3. After the below ground installs are done. Grade the area between the homes so it is smooth along both sides of the property line but with a shallow nice looking swale at the center.
4. Install "steps" along both sides of the property line using pavers, etc.
5. Install a non eroding lining in the center swale that is the steep part of the hill.
6. Install "Rip Rap" rock to cover the swale from the base of the hill to the top. Also on the flats above if that works. No Photo so verify.
a) Note: Rip Rap rock is a type of pattern of broken rock that makes them interlock, the opposite from smooth river rock. You might see it on commercial or city and county drain culverts in town, and on steep grade drainage swales. The rocks do not tumble in heavy water wash from hard rainfall.

Note: Do the above with the heaviest expected rainfall in mind. AKA: (100 year flood) is called in some counties. If you do that, then any lighter rainfall will all be a "non issue".

End Goals:
1. Complete peace of mind and the issue is solve and done with.
2. Everything is done tastefully to keep up the value of the property, looks great, and is a functional measure.
3. Do things once and once only. If things are done "Mickey Mouse" here and there to cut corners or save costs, etc, then it will come back with more water and erosion issues in the future.
4. With this type of steep slope and the water erosion shown, planting anything to be a cure or solve anything is futile.
5. If the heavy erosion cut is the property line, then maybe the neighbor can split costs with you?
6. Hire reputable licensed and insured contractors only. Get multiple bids. Be sure they are all bidding on the same work and products used.

I hope this is helpful for you.
j
(insert standard dislaimer for opinionizations and onions and so forth).
*I've hired subs many many times for this type of thing and every project is a little different in design to take care of the problem for good. We've also done many that were done poorly by DIY owners, etc, or other subs and turned into disasters after heavy storms. There are many ways to design something to solve your water drainage problem, this is just one or some options noted in the missive above.
Sounds grrreat!
Notes;
1. Depending on the input, the main smooth bore central drain line that carries the water from the downspouts of both homes might be upsisized. It would have to be calculated. IE: 4 downspout outlets from 4 inch smooth PVC/ABS into one 6 inch or 8 inch central pipe. Depends on rain volume at its max, etc. It is often cheaper and easier to handle running (two) 4 inch central drain lines since fittings are cheaper and easier to find, etc.
2 Be sure to use angle "sweeps" vs "elbows or T's", for the taps to the central lines. It's the same as plumbing dwv drain lines in concept and shapes.
3 Not sure of area, but bury below frost line if freezing temps are there.
4 Adequate "clean outs" here and there so the pipes can be cleaned out if they get plugged with leaves, dead rats, etc.
5 This also prevents erosion from the home foundation footings, etc. (important), So design and plan that landscaping accordingly.
6 "Jagged Rip Rap" rock and good barrier will follow a sloped drainage swale and slow the water down. There's no need to cut up the hill to terrace it. Stepped pavers on each side to walk up and down also covers the soil and prevents erosion. The landscapers can just adjust the rise/run as they install it to follow the hill slope.
7. Sometimes landscapers use "KeyStone" types of interlocking block to handle steep slopes terracing , but given the pictures, not sure if this is needed.

** Do everything possible to protect the home foundation/footings on each side from settling, water intrusion, etc, by keeping the slope and grade of that center dirt section as close as possible to the way it was intended when it was first built. Thus, do not disturb by cut terracing, etc.

glad to hear that the neighbor is positive and on board, that really helps a whole lot.
j
Last edited by Sandtrap on Wed Mar 22, 2023 9:43 am, edited 1 time in total.
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Bcdkgf
Posts: 310
Joined: Sat Aug 01, 2020 9:43 am
Location: Florida

Re: Yard Drainage Question

Post by Bcdkgf »

Mr. Rumples wrote: Sun Mar 19, 2023 9:20 am Due to the proximity to the house, the slope and the climate, I would put in a cinder block or concrete block terrace and fill it with stone. It would be a one time expense; while concrete blocks would require a base, cinder blocks are more forgiving if one wants an unfinished look - though technically they would need one. Instead of stones, the fill could be compost/dirt/leaves with plants. Liriope would work since their roots are strong, store water, and they thrive on neglect, but there are most likely native plants which would work. The problem with plants is even the ones which thrive on neglect will need some maintenance and they might provide a home for mice or other critters. Decking 4x4's would also work since they are treated for insects.

I know stone was mentioned as being difficult to get to the spot, but with labor it can be dumped via a wheelbarrow. This is something a landscape company might take on. I had a septic tank collapse and they had to fill that void with stone - an entire dump truck load had to hauled via wheelbarrows to the side of the house - trees blocked truck access.
My county in Georgia (Gwinnett) gave us two dump trucks worth of granite chunks, rip-rap, for free. Just contact your county We carried it in an wheel barrel and a riding mower yard trailer. It was a ton of work, best done in cooler weather. Your erosion is nothing compared to what we had. In your situation I would lay the rock down and intersperse liriope (monkey grass, spider grass). I used monkey grass in other locations to slow water down, build the soil back up and it worked!

The rip-rap eventually gets covered over.
Women and men plan, the Gods laugh.
Topic Author
LifeIsGood
Posts: 1243
Joined: Mon Feb 11, 2008 7:43 pm
Location: Atlanta, GA

Re: Yard Drainage Question

Post by LifeIsGood »

Can't believe you got free rip rap. Unfortunately I live in Fulton county and the city of Johns Creek. I might call Johns Creek. They are much easier to deal with. I live in a gated community so I suspect they will say "No dice".
Bcdkgf wrote: Mon Mar 20, 2023 9:32 am
Mr. Rumples wrote: Sun Mar 19, 2023 9:20 am Due to the proximity to the house, the slope and the climate, I would put in a cinder block or concrete block terrace and fill it with stone. It would be a one time expense; while concrete blocks would require a base, cinder blocks are more forgiving if one wants an unfinished look - though technically they would need one. Instead of stones, the fill could be compost/dirt/leaves with plants. Liriope would work since their roots are strong, store water, and they thrive on neglect, but there are most likely native plants which would work. The problem with plants is even the ones which thrive on neglect will need some maintenance and they might provide a home for mice or other critters. Decking 4x4's would also work since they are treated for insects.

I know stone was mentioned as being difficult to get to the spot, but with labor it can be dumped via a wheelbarrow. This is something a landscape company might take on. I had a septic tank collapse and they had to fill that void with stone - an entire dump truck load had to hauled via wheelbarrows to the side of the house - trees blocked truck access.
My county in Georgia (Gwinnett) gave us two dump trucks worth of granite chunks, rip-rap, for free. Just contact your county We carried it in an wheel barrel and a riding mower yard trailer. It was a ton of work, best done in cooler weather. Your erosion is nothing compared to what we had. In your situation I would lay the rock down and intersperse liriope (monkey grass, spider grass). I used monkey grass in other locations to slow water down, build the soil back up and it worked!

The rip-rap eventually gets covered over.
Bcdkgf
Posts: 310
Joined: Sat Aug 01, 2020 9:43 am
Location: Florida

Re: Yard Drainage Question

Post by Bcdkgf »

LifeIsGood wrote: Tue Mar 21, 2023 5:08 am Can't believe you got free rip rap. Unfortunately I live in Fulton county and the city of Johns Creek. I might call Johns Creek. They are much easier to deal with. I live in a gated community so I suspect they will say "No dice".
Bcdkgf wrote: Mon Mar 20, 2023 9:32 am
Mr. Rumples wrote: Sun Mar 19, 2023 9:20 am Due to the proximity to the house, the slope and the climate, I would put in a cinder block or concrete block terrace and fill it with stone. It would be a one time expense; while concrete blocks would require a base, cinder blocks are more forgiving if one wants an unfinished look - though technically they would need one. Instead of stones, the fill could be compost/dirt/leaves with plants. Liriope would work since their roots are strong, store water, and they thrive on neglect, but there are most likely native plants which would work. The problem with plants is even the ones which thrive on neglect will need some maintenance and they might provide a home for mice or other critters. Decking 4x4's would also work since they are treated for insects.

I know stone was mentioned as being difficult to get to the spot, but with labor it can be dumped via a wheelbarrow. This is something a landscape company might take on. I had a septic tank collapse and they had to fill that void with stone - an entire dump truck load had to hauled via wheelbarrows to the side of the house - trees blocked truck access.
My county in Georgia (Gwinnett) gave us two dump trucks worth of granite chunks, rip-rap, for free. Just contact your county We carried it in an wheel barrel and a riding mower yard trailer. It was a ton of work, best done in cooler weather. Your erosion is nothing compared to what we had. In your situation I would lay the rock down and intersperse liriope (monkey grass, spider grass). I used monkey grass in other locations to slow water down, build the soil back up and it worked!

The rip-rap eventually gets covered over.
I had an erosion control engineer from the county inspect and he agreed to the county sending us the riprap. Part of your real
estate taxes are for drainage and erosion control. Try calling your county for the appropriate department. We had seven acres full of gullies/streams and our driveway was in danger of falling into one of them. That stuff certainly slows the water down and the soil builds back up. Ferns were also planted to help contain soil from washing away. I wish I had pictures, it was such a lovely place. I miss it, but not the work.
Women and men plan, the Gods laugh.
Topic Author
LifeIsGood
Posts: 1243
Joined: Mon Feb 11, 2008 7:43 pm
Location: Atlanta, GA

Re: Yard Drainage Question

Post by LifeIsGood »

The fly in the ointment is that we live in a gated community which means that Fulton County and the city of Johns Creek both tell me I'm on my own since the HOA owns the infrastructure.
Bcdkgf wrote: Tue Mar 21, 2023 8:37 am
LifeIsGood wrote: Tue Mar 21, 2023 5:08 am Can't believe you got free rip rap. Unfortunately I live in Fulton county and the city of Johns Creek. I might call Johns Creek. They are much easier to deal with. I live in a gated community so I suspect they will say "No dice".
Bcdkgf wrote: Mon Mar 20, 2023 9:32 am
Mr. Rumples wrote: Sun Mar 19, 2023 9:20 am Due to the proximity to the house, the slope and the climate, I would put in a cinder block or concrete block terrace and fill it with stone. It would be a one time expense; while concrete blocks would require a base, cinder blocks are more forgiving if one wants an unfinished look - though technically they would need one. Instead of stones, the fill could be compost/dirt/leaves with plants. Liriope would work since their roots are strong, store water, and they thrive on neglect, but there are most likely native plants which would work. The problem with plants is even the ones which thrive on neglect will need some maintenance and they might provide a home for mice or other critters. Decking 4x4's would also work since they are treated for insects.

I know stone was mentioned as being difficult to get to the spot, but with labor it can be dumped via a wheelbarrow. This is something a landscape company might take on. I had a septic tank collapse and they had to fill that void with stone - an entire dump truck load had to hauled via wheelbarrows to the side of the house - trees blocked truck access.
My county in Georgia (Gwinnett) gave us two dump trucks worth of granite chunks, rip-rap, for free. Just contact your county We carried it in an wheel barrel and a riding mower yard trailer. It was a ton of work, best done in cooler weather. Your erosion is nothing compared to what we had. In your situation I would lay the rock down and intersperse liriope (monkey grass, spider grass). I used monkey grass in other locations to slow water down, build the soil back up and it worked!

The rip-rap eventually gets covered over.
I had an erosion control engineer from the county inspect and he agreed to the county sending us the riprap. Part of your real
estate taxes are for drainage and erosion control. Try calling your county for the appropriate department. We had seven acres full of gullies/streams and our driveway was in danger of falling into one of them. That stuff certainly slows the water down and the soil builds back up. Ferns were also planted to help contain soil from washing away. I wish I had pictures, it was such a lovely place. I miss it, but not the work.
Mr. Rumples
Posts: 2978
Joined: Sun Aug 25, 2019 7:16 am

Re: Yard Drainage Question

Post by Mr. Rumples »

I live in the Chesapeake Bay watershed. There is a program for assisting homeowners to ensure runoff into the watershed is reduced. They sent an agronomist to visit me, hence the rain garden idea.

The OP lives in the Upper Chattahoochee watershed, perhaps they have something similar: https://chattahoochee.org/watershed-map/

Does the HOA own this land or the individual homeowner?

Update: I recall, that the Chesapeake Bay folks had a reimbursement / grant program for homeowners. There was a separate one for businesses and non-profits including HOA's. I did the work myself, so chose not to use it.
Last edited by Mr. Rumples on Wed Mar 22, 2023 6:37 am, edited 1 time in total.
"History is the memory of time, the life of the dead and the happiness of the living." Captain John Smith 1580-1631
RubyTuesday
Posts: 2241
Joined: Fri Oct 19, 2012 11:24 am

Re: Yard Drainage Question

Post by RubyTuesday »

I’m no expert but have recently learned that sediment is the biggest and most problematic pollutant to many watersheds. Often storm sewers dump unfiltered water (and corresponding pollutants) directly into streams.

As we build our house on our steep slope lot we are trying to design a landscape plan that captures and manages all the water that falls on our property. There are landscape architects (for a fee) and watershed stewardship organizations (perhaps for free) whose advice would likely be helpful.
“Doing nothing is better than being busy doing nothing.” – Lao Tzu
RubyTuesday
Posts: 2241
Joined: Fri Oct 19, 2012 11:24 am

Re: Yard Drainage Question

Post by RubyTuesday »

Mr. Rumples wrote: Wed Mar 22, 2023 5:04 am I live in the Chesapeake Bay watershed. There is a program for assisting homeowners to ensure runoff into the watershed is reduced. They sent an agronomist to visit me, hence the rain garden idea.

The OP lives in the Upper Chattahoochee watershed, perhaps they have something similar: https://chattahoochee.org/watershed-map/

Does the HOA own this land or the individual homeowner?
+1

OP - have you reached out to the Chattahoochee Riverkeepers?
“Doing nothing is better than being busy doing nothing.” – Lao Tzu
Topic Author
LifeIsGood
Posts: 1243
Joined: Mon Feb 11, 2008 7:43 pm
Location: Atlanta, GA

Re: Yard Drainage Question

Post by LifeIsGood »

"Does the HOA own this land or the individual homeowner?"
I own the land that has the runoff issue but the HOA owns the storm sewer drain system that the water enters into.
I'll touch base with the Chattahoochee River Keepers and see what they say. I've heard of them but never considered them entering into this equation.
Mr. Rumples
Posts: 2978
Joined: Sun Aug 25, 2019 7:16 am

Re: Yard Drainage Question

Post by Mr. Rumples »

I removed all of my underground drainage pipes and replaced them with surface runnels. I want to see that everything is flowing without having to go out in the rain and ensuring they were working. The other factors were one was clogged, and then when I removed two, those waterbeds - which are really roaches - were in them. There is an ongoing debate where I live among professionals (videos also on the internet) as to which works best, smooth, smooth with holes or corrugated. Fans of the latter say it creates a turbulence which helps keep blockages out. I don't know, I just am happy with my runnels. http://getyourbotanyon.blogspot.com/201 ... ening.html

Its also kind of fun to watch the runnel in action, but then again, my life is kind of boring...It's a bit more fun than watching paint dry.
"History is the memory of time, the life of the dead and the happiness of the living." Captain John Smith 1580-1631
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