How to exit a drain pipe from a hillside

   / How to exit a drain pipe from a hillside #1  

Travelover

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I need to exit a 4" plastic pipe from a french drain from a hillside that is also part of my lawn. I'm trying to think of a design that is not a trip hazard, won't get hit by my mower, won't clog up and isn't too ugly.

If I just cut off the pipe at the same angle as the hillside I have a trip hazard and the top lip of the pipe will probably be exposed as the soil is so thin there.

One idea that I have is to weld up a grill that would lay flat into the ground and have the water discharge through it. I'm not sure if the grill would tend to move around (Michigan winters), or if the grill would clog easily. The pipe will also be hooked to a drain near my garage apron, which may take in a few leaves.

Anybody done something similar?
 

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   / How to exit a drain pipe from a hillside #2  
There are galvanized discharge outlets available that we use on highway shoulder drains, but all that I've used were for steeper slopes than you're showing and would still need a grille to not trip and mow over them. You're probably better off just making a grille as you mentioned. I'd suggest one with pins driven into the ground to prevent movement.
 
   / How to exit a drain pipe from a hillside #3  
I always use a grated catch basin reversed to the water flows out of the basin...

Nice and level, no tripping hazard.
 
   / How to exit a drain pipe from a hillside #4  
I live in S Illinois and I have a couple drains close to what you are working with. The freeze issue is a concern. I had to dig the pipe back into the hill and ditch the drain to grade. That way the ground is covering more pipe and helps keep it down. It still raises some, but it is workable. I would guess up there it would be even worse. I also went back a few feet and increased the pipe size so it has more room to handle the water freezing at the exit.
 
   / How to exit a drain pipe from a hillside #5  
Sorry... didn't account for freeze conditions... it never happens here where I live in California.
 
   / How to exit a drain pipe from a hillside #6  
Here's a couple of pictures showing how I handled that situation. The first picture was taken during installation a couple of years ago. The second picture was taken very shortly after Tropical Storm Lee came through last Sunday.
 

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   / How to exit a drain pipe from a hillside #7  
I used one of the inlet boxes that are about 6x6 square and cut the bottom out and put it on stone the excess water comes out the grate over the top the rest soaks in the stone to drain it

12catchbasin145x180.jpg
 
   / How to exit a drain pipe from a hillside #8  
Is there a reason you don't want to use gravel? The right sized gravel should maintain the grade and allow the water to flow through it.
To expand on the thought, a "dry well" could be extended just below grade below the end of the pipe which could be covered with a membrain and seeded or sodded over?
 
   / How to exit a drain pipe from a hillside #9  
Is there a reason you don't want to use gravel? The right sized gravel should maintain the grade and allow the water to flow through it.
To expand on the thought, a "dry well" could be extended just below grade below the end of the pipe which could be covered with a membrain and seeded or sodded over?

I thought about that idea as well but then remember the OP mentioning the grage apron may tie into this line so debris is a concern and stone would eventually plug up with leaves and other debris introduced from the gutter. So it would be a maintance issue having to dig up the stone every so often to clear out any garbage that made it in.

I personally would just cut the pipe flush and see what happens. I don't see it being a trip hazard as once its there people will get use to it and if they find themselves tripping over it often, well, don't ever let them drive. But if it does become a problem you can always adapt a grate after the fact. Mowing, just straddle over the opening and don't worry. I would be more worried about mowing over a steel grate and having it pop up under the deck destroying the blades, if the plastic pipe rises some how the mower won't even notice.
 
   / How to exit a drain pipe from a hillside #10  
I thought about that idea as well but then remember the OP mentioning the grage apron may tie into this line so debris is a concern and stone would eventually plug up with leaves and other debris introduced from the gutter. So it would be a maintance issue having to dig up the stone every so often to clear out any garbage that made it in.

I personally would just cut the pipe flush and see what happens. I don't see it being a trip hazard as once its there people will get use to it and if they find themselves tripping over it often, well, don't ever let them drive. But if it does become a problem you can always adapt a grate after the fact. Mowing, just straddle over the opening and don't worry. I would be more worried about mowing over a steel grate and having it pop up under the deck destroying the blades, if the plastic pipe rises some how the mower won't even notice.


I re-read the OP and realized the same thing about the leaves etc...
 
 
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