PDA

View Full Version : Mulch Drainage Issue


Roachy
03-03-2012, 11:26 AM
One of my customers is having drainage issues in his backyard. I am looking for advice on the best way to alleviate this problem. I have drawn a pretty rough looking picture of his backyard. The bottom of the picture is where his deck is, the olive green is his fence, the ring in the middle is patio pavers, and the brown is all mulch. His backyard is sloped on a slight angle towards the fence, and during a heavy rainfall, all that rain washes the mulch against the fence making a big mess. One storm pushed part of the fence apart. THe arrows show the direction of water flow, and the red circle I made shows where most of the rain and mulch drain to.

Any advice on allowing for better drainage. The mulch and dirt is about 6in thick along the back side of the fence.

45ftx45ft

http://img140.imageshack.us/img140/2561/backyarddrawing.jpg (http://imageshack.us/photo/my-images/140/backyarddrawing.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

32vld
03-03-2012, 07:59 PM
Problem is not that the water does not drain the problem is where is all the water coming from?

How steep is the grade?

LindblomRJ
03-03-2012, 09:14 PM
What is the soil type? How long does the water remain in the area? What is the slope towards the fence and beyond the fence?

I am guessing the dirt and much are creating a dam along the fence. If cleaning up that area of the dirt and much to remediate the pooling.

If that doesn't work there are two options would be a dry well. The second is making sure the grade slopes all the way away from the area where is pools.

Roachy
03-03-2012, 09:16 PM
The backyard only has a slight slope, maybe 5 degrees. And the water just runs off the patio area and just flows toward the fence and then the mulch starts to pile up which pushes out the bottom of the fence. The backyard slopes so I cant change the grade, and I have shoveled everything away and it just dams up again a few storms later. Not sure what a dry well is.

Procut lawn expert
03-03-2012, 09:36 PM
i would just put a french drain in front of the mulch and on the side it mostly goes to make a french drain under the mulch and fence to were it will not wash the mulch away it will be under ground when it gets to the mulch . with the drain you can put mulch back over the drain and never be able to see it there . just put a thin layer of creek rock over the french drain in front of the mulch and it will look like a boarder you could even do it up to the fence and some more somewhere else to make it look like some designing in the mulch with creek rock to make it match not just be in the one place .

Roachy
03-03-2012, 10:13 PM
Thanks procut, hope that might work. How big are the holes you typically make in a drainage pipe for something like this, and should I wrap it in landscape fabric before I cover it with gravel?

LindblomRJ
03-03-2012, 10:15 PM
The backyard only has a slight slope, maybe 5 degrees. And the water just runs off the patio area and just flows toward the fence and then the mulch starts to pile up which pushes out the bottom of the fence. The backyard slopes so I cant change the grade, and I have shoveled everything away and it just dams up again a few storms later. Not sure what a dry well is.
Sigh... I'd say it could be a learning experience. However drainage is nothing you want to *mess* around with if you have no clue.
i would just put a french drain in front of the mulch and on the side it mostly goes to make a french drain under the mulch and fence to were it will not wash the mulch away it will be under ground when it gets to the mulch . with the drain you can put mulch back over the drain and never be able to see it there . just put a thin layer of creek rock over the french drain in front of the mulch and it will look like a boarder you could even do it up to the fence and some more somewhere else to make it look like some designing in the mulch with creek rock to make it match not just be in the one place .

A french drain would also work.

Details like soil type. Slope is usally measure rise (or fall) over run. For every 10 feet the grade drops 4 inches. If there is slope away from the house it sounds like mulch and dirt are causing a dam. So the mulch seems to be the problem. So either remove the much and create a dry stream bed or something along those lines. River rock would work. Or a better ground cover that doesn't wash away any time there is a rain.

A better ground cover would be best IMO. French drains and dry wells have a purpose, they can plug or fail from time to time.

Smallaxe
03-04-2012, 11:03 AM
The rain needs to be stopped before it reaches the fence... right off the pavers would be the place to modify drainage...

Is that a 'ring of pavers' or 'solid circle' of pavers??

White Gardens
03-04-2012, 11:16 AM
The rain needs to be stopped before it reaches the fence... right off the pavers would be the place to modify drainage...

Is that a 'ring of pavers' or 'solid circle' of pavers??

I was thinking the same thing.

Put a small rock bed or bed of some sort at the edge of the patio to slow the water down and try to direct it to the sub-soil.

Problem with a french drain is where to make an exit point. if there is one, I'd put in a small drainage system and two dry wells buried in there somewhere.

Here is a link to a down-spout drainage project on a back-yard, It has a catch basin it in to slow the water down as much as possible before exiting.

https://www.facebook.com/media/set/?set=a.10150202909217643.313599.185135107642&type=3

Here is also a link to a french drain system I installed. I call the HO from time to time and he says he's pretty much eliminated water getting into the basement. No catch basin as I was able to exit the drain on the backside of the house.

https://www.facebook.com/media/set/?set=a.212043232642.134331.185135107642&type=3


Roachy, can you post any photos of the property?

.....

shovelracer
03-04-2012, 12:43 PM
You can start by putting in a culvert or two.

Procut lawn expert
03-04-2012, 01:00 PM
They have that new pipe that has that foam around it .thats what i use in my drains .i dig them about 18 inches deep put the pipe in then put drain rock in then put creek rock if you want it to look natural or you can put mulch back over it to hide it . Really should just put them big enough to handle the amount of water you're dealing with .18 inches will take a lot of water you could run it down the edge of the patio or the edge of the mulch the just run some off of it under the fence

Kiril
03-04-2012, 01:05 PM
Doesn't anyone here actually calculate drainage requirements, or do we just engage in guesswork and hope it works?

Roachy
03-04-2012, 06:12 PM
Thanks for the ideas guys. My sketch drawing wasnt the most accurate. The pavers form a track in the backyard for their dogs to run on, and inside of the track is mulch and river stone. In the first picture, you are looking away from the deck and toward the lower part of the backyard. In the second picture, the fence on the right side of the picture is the low part of the backyard, and that patio swing is where most of the water drains to. There is drainage system installed in the ground right outside the fence near the patio swing. After a heavy rain, the water washes all the mulch against the fence making a big muddy mess. I am leaning toward putting a french drain right past the pavers at the bottom of the backyard so the water can drain through the fence easier and toward that underground drainage system.


http://img26.imageshack.us/img26/474/cialfibackyard.jpg (http://imageshack.us/photo/my-images/26/cialfibackyard.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

http://img28.imageshack.us/img28/5921/cialfibackyard2.jpg (http://imageshack.us/photo/my-images/28/cialfibackyard2.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

http://img42.imageshack.us/img42/6106/cialfibackyard3.jpg (http://imageshack.us/photo/my-images/42/cialfibackyard3.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

LindblomRJ
03-04-2012, 06:40 PM
Doesn't anyone here actually calculate drainage requirements, or do we just engage in guesswork and hope it works?

Evidently not. I am not that impressed at the pictures and it is not surprising they have issues in the back yard. :rolleyes:

So they resort to the SWAG (silly wild assed guess) method of drainage management.

3rdDayBrad
03-04-2012, 07:09 PM
All great suggestions/solutions, guys. May I suggest creating a dry riverbed in the area where the water is draining to? Since the water is already going there, why fight it? Just put in a riverbed, and when it rains, the water will just flow over the rocks and on to wherever it is already heading. Good luck with your project!

Procut lawn expert
03-04-2012, 09:39 PM
why would you have to waste you time to calculate drainage for something that small ??? put what you know would more than enough water out . i mean he is not doing the sub grade one a commercial project or sub division . then maybe you wouldn't want to just guess it .

Kiril
03-04-2012, 09:49 PM
why would you have to waste you time to calculate drainage for something that small ???

1) Because that is what professionals do.

2) So you don't end up with the problem the guy is having now after the landscaping/hardscaping is done.

3) So you don't appear like an amateur hack to your clients.

Procut lawn expert
03-04-2012, 10:22 PM
well if you know anything about it you should be able to do something that small off the top of your head . i am no flaming to be a professional excavator but in a french drain all you have to know is permeability foot per sec, area normal to flow per sec ,flow line slop,
area foot of drain trench . i'm not sure but if you don't even know that much you should't be doing the drain job call in the back up .

Roachy
03-04-2012, 11:38 PM
Thanks for the responses. Im pretty sure no one here is going to calulate water flow mathematically here. Technically I could attempt to calculate the inflow of water over the backyard in a minute, and make sure my drainage could support that rate in outflow per minute but that does not need to be done for this scale. And yes I will make sure my pipe is large enough to support enough outflow of water.

My questions are what professional advice and suggestions would you guys give to help in this situation. How would you guys go about doing this. Yes I am a professional, but I deal mostly in maintenance and do not have the most experience in drainage or excavating.

My plans so far are to install a french drainage sytem along the back fence. Probably dig 12-18in down. Use gravel, fabric, piping etc. Route the water underneath the fence so it is not dammed up thus allowing it to flow outside to the underground drainage. Sound good?

LindblomRJ
03-04-2012, 11:44 PM
All great suggestions/solutions, guys. May I suggest creating a dry riverbed in the area where the water is draining to? Since the water is already going there, why fight it? Just put in a riverbed, and when it rains, the water will just flow over the rocks and on to wherever it is already heading. Good luck with your project!

That would make sense. And you wouldn't tear up the yard digging a french drain or having any of the other expeses. And you will know it will always work and never plug up or have other headaches.

LindblomRJ
03-05-2012, 12:03 AM
Thanks for the responses. Im pretty sure no one here is going to calulate water flow mathematically here. Technically I could attempt to calculate the inflow of water over the backyard in a minute, and make sure my drainage could support that rate in outflow per minute but that does not need to be done for this scale. And yes I will make sure my pipe is large enough to support enough outflow of water.

My questions are what professional advice and suggestions would you guys give to help in this situation. How would you guys go about doing this. Yes I am a professional, but I deal mostly in maintenance and do not have the most experience in drainage or excavating.

My plans so far are to install a french drainage sytem along the back fence. Probably dig 12-18in down. Use gravel, fabric, piping etc. Route the water underneath the fence so it is not dammed up thus allowing it to flow outside to the underground drainage. Sound good?

There is a time and a place for a french drain. I am of the opinion that this isn't the best fix for this area. There are others who disagree with me, that is fine.

Here is my thought looking at the pictures and looking at the problem, it isn't a slope issue, it is fence and a mulch issue.

Beyond the fence there is evidently french drain system in place. So the drainage was apparently don't correctly before you were called to the site. The problem happens with the mulch is carried to the fence and plugs up the outlet. The idea of clearing the path of the mulch and adding fabric under river rock to create a dry stream effect. There is already rock back there, so the dry stream bed will not look out of place and will fit in really nicely.

The advantages, you are using the surface to your advantage, it is already there. Next you dig up a yard and drop a franch drain which is well and good, but you have to dump the water out somewhere. I am guessing that will lead an outlet lower than drains on the other side of the fence. That is creating more work and headache for you.

Procut lawn expert
03-05-2012, 07:42 AM
thats what i would do you will not have to worry about it anymore if you do the french drain 18 inches put drain rock about 3 inches from the top of the ground then put river rock or those rock they already have. i would go bye lowes or if you have a john deere landscapes they have the pipe that is a french drain pre made all you do is dig it out put the pipe in then put you rock down i would just fill the rest up with drain rock because it is cheaper then put your landscape rock over it to make it look good.. i have put in 346 french drains and i give a two year guarantee on it that if they have any trouble i will come back and fix it and i have not been back in 10 years to fix one yet .

Smallaxe
03-05-2012, 08:13 AM
The impression I got from those pictures, is that the paver pathway is the low spot and as water builds up, the ground saturates...
Because there are probably puddles between the mulch and the river stone, could be the reason for the dirt marks on the stone pile... That river stone should be lower than the pavers and it should collect the majority of the water from the impermeable surfaces...

You didn't mention dogs before... the dogs are moving the mulch and the rain is just moving the dirt, for the most part...

White Gardens
03-05-2012, 12:31 PM
The impression I got from those pictures, is that the paver pathway is the low spot and as water builds up, the ground saturates...
Because there are probably puddles between the mulch and the river stone, could be the reason for the dirt marks on the stone pile... That river stone should be lower than the pavers and it should collect the majority of the water from the impermeable surfaces...

You didn't mention dogs before... the dogs are moving the mulch and the rain is just moving the dirt, for the most part...

Exactly.

The grade of the beds is too high in relation to the sidewalk.

Either drop the grades of the beds, or do some sort or restraint along the sidewalk. Personally I would drop the grade of the beds as I don't like the look of raised edging along the pavers.

....

tyler_mott85
03-05-2012, 05:04 PM
All great suggestions/solutions, guys. May I suggest creating a dry riverbed in the area where the water is draining to? Since the water is already going there, why fight it? Just put in a riverbed, and when it rains, the water will just flow over the rocks and on to wherever it is already heading. Good luck with your project!


This is my immediate idea for this problem. Since there is a drain on the other side of the fence as the OP stated I would just open up a way for the river to run. Make sure as others have said that the finished grade of the river bed is lower than the pathway. This isn't the level of the ground before the rock this is the level of the river bed when all is said is done. After pictures would be just swell. :dancing:

White Gardens
03-05-2012, 05:56 PM
Only other suggestion I have is to add a lot more plantings in their to help hold the soil.

The biggest problem is that paver path seems like it was installed too low in relation to the fence also.

....