French type drains on a steep side hill

[breadtrk]

Right out my back door, the land goes uphill about an 40 degree angle for about 40 ft. I get lots of rain run off from the slope above that, that washes the hill down onto my foundation until it starts washing over the foundation and I dig it back out. I've done this for the last 30 years with picks and shovels. I now have a tractor with a hoe on it.

I'm thinking of using the hoe to dig trenches that start high and run diagonal down the slope to fill with rock and give that water somewhere else to go. Sort of Chevron shaped with the house in the wide part of the chevron below it if that makes sense.

The hill is too steep for me to setup on sideways to dig, and I'm just not comfortable sitting on it diagonal either. SO I'm thinking I should terrace it. I can go up and down on this hill fine so I was thinking of using the backhoe to dig and drag, then move and repeat. Then make my trenches next year after that has time to settle. I simply can't afford to rent or buy a dozer, I have to use what I have here.

Any tips or serious flaws in my plan?

 

[tractorshopper]

I've never done this, so my advice may not be great, but if that is your plan, I'd angle the terrace you are building back into the slope itself some so that in the year you are waiting for it to settle, that runoff will channel along the inside edge of the terrace and run off away from your house in the direction you want it to.

I have a similar situation our the back and side of my house. I've used my box blade to create a small swale at the bottom of it to keep the water from getting too close to the house and it channels it out behind my garage and into the woods. I'll attach a picture if I can to give you an idea.

 

[tractorshopper]

Oh well, I tried again but I haven't been able to attach a picture on here in about a week or more. I apologize.

 

[tractorshopper]

You can see it in my avatar below my loader bucket. In this picture, it's the back of my house you see and the land is swaled beside and behind my house down below grade of the house foundation such that the hill that I get all the runoff from is what my tractor is parked on. The water runs along the edge of the hill below my loader toward where I took the picture from.

 

[breadtrk]

I've never done this, so my advice may not be great, but if that is your plan, I'd angle the terrace you are building back into the slope itself some so that in the year you are waiting for it to settle, that runoff will channel along the inside edge of the terrace and run off away from your house in the direction you want it to.

I have a similar situation our the back and side of my house. I've used my box blade to create a small swale at the bottom of it to keep the water from getting too close to the house and it channels it out behind my garage and into the woods. I'll attach a picture if I can to give you an idea.

And there is why I posted! That is so freaking simple and brilliant. If that works well, there will be no need to come back later.

 

[breadtrk]

I've never done this, so my advice may not be great, but if that is your plan, I'd angle the terrace you are building back into the slope itself some so that in the year you are waiting for it to settle, that runoff will channel along the inside edge of the terrace and run off away from your house in the direction you want it to.

I have a similar situation our the back and side of my house. I've used my box blade to create a small swale at the bottom of it to keep the water from getting too close to the house and it channels it out behind my garage and into the woods. I'll attach a picture if I can to give you an idea.

And there is why I posted! That is so freaking simple and brilliant. If that works well, there will be no need to come back later.

 

[boggen]

dig out the hill and put up a wall, and level the area out below
or...put a wall up. and fill in dirt behind the wall. to bring the area up behind the wall up.

both of above... still means putting a french drain behind the wall with some rock. to allow for correct drainage to happen. and possibly putting a french drain between wall and house. to help deal with any extra drainage that might be needed in the given area.

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or perhaps, at bottom of hill. dig out a trench across the hill side, put your french drain hose / pipe down, and then fill right up to ground level with rock. ((kinda of a digging a creak along the hill side, but then filling it in with rock, to keep dirt from washing away. and at same time filling up the trench. so there is no long hole to deal with.

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i am some what against diagonal or trenches that goes straight down the hill. vs across it like noted above.
why am i against it? it could be possible to create a vacuum / suction, higher up the hill that sucks dirt into the slots of the french drain and clog it. and then possibility of french drain clogging "down stream" some place forcing water to come out through the hill side causing a large sudden wash out. other words, long term (as in years), you are more looking at a failure happening.

running french drain across the hill. if the drain gets clogged, it just spills over right were it comes in, and no big deal. (within reason)

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run off water (as in actual heavy rains), and not water that is soaking through the ground. sounds more to be of the issue. a french drain takes time for water to soak through the dirt. your needing more of a "flash flood" control, and reason why i mentioned above, of digging right at bottom of hill, and put in in a french drain, and filling right up to ground level with rock. it allows all the water to dump directly into the french drain pipe/hose. i suppose you could do some "grating" vs rock. say taking a "rain gutter" on side of your house. and dropping it right into the ground. so top of edge is just a little bit below ground level. and placing grating on top of it. might work.

 

[Gary Fowler]

I suppose you could do some "grating" vs rock. say taking a "rain gutter" on side of your house. and dropping it right into the ground. so top of edge is just a little bit below ground level. and placing grating on top of it. might work.

. This sounds like the best idea and you wont have to disturb the hill creating possible flash flood wash out of the loose soil.
It will take a bit more than a rain gutter to handle the water though. I would think a sloping trench or swale of at least 3-4 feet wide by 1-1.5 feet deep(depth to be after rock lining) and lined with large rocks to prevent erosion would work. Just as gentle a slope as you can get would work, you don't want rapids forming in the run off.

 

[dave1949]

If you slope the terrace into the hillside as suggested, do you worry about saturating the hillside below the terrace? It sounds like creating a lump on the hillside that will saturate and may wash down the hill in large quantities. Depends on your soil I guess.

I would also try to give each terrace a high point that corresponds to roughly the center area of your house below. That would divert runoff to the sloped sides of the terraced area.

 

[breadtrk]

I think I understand what you mean. I'll get some pictures this weekend and make some scribbles in paint to illustrate. I think the high point you mention is the top of my Chevron. Be it a terrace, drain, ditch, the goal is to give the water someplace to go besides straight down.