[Drafto]

This is my first post on here so forgive me if I do not do something right.

I was asked by a new customer to submit a proposal from a design idea I had for her front hill. The hill is very steep, rises 12' over 30' in one spot then softens from about 18' over 70' in another place. You may be able to tell from the pictures what I am talking about. She would like a large boulder (2'-3') wall like my plan below, I have never heard of an engineered dry laid boulder wall, but I am thinking I should contact an engineer prior to estimating. I am not sure if I am being too cautious or not. Have any of you ever laid a 2 tier boulder wall? I am just looking for some input. The bottom wall (neither wall is shown to scale) will be 90' long by 4' high, and the second which will be about 8 ' away from the first if 70' long by 4' high.

I am having trouble posting pictures.

Dan

[Drafto]

Got it:

[Drafto]

Next:

[Drafto]

Another shot:

[Drafto]

And finally my design:

[Drafto]

And finally, how much time will it take me to place 120 tons of boulders with an excavator with clamps, and 1 laborer.

Any help that you guys can provide is very much appreciated.

Thanks,
Dan

[Paul]

The walls you show are very do able. I like to use fabric and gravel behind mine. Time wise it hard to tell but looking at 120 tons My guess is close to 200 to 250 hours depending on how close you match each boulder to the next. You might speed things up some by using a skid steer to get the stones closer to the site, moving gravel and removing spoils.

As far as engineering the walls not many will do that with out some information on how your going to tie them into the slope. There are not too many ways to do this that one could call standard practice. So I don't think it would be a cost effective.
A good shoulder, bury the base stones by 1/3, and slope each stone above the lower ones so you have little overhang and have at least 8'-10 feet between each 4' wall would work. Remember your using weight here to hold back the soil so I'm figuring your going to be short by about 20 to 30 tons of stone, if you bury the first course 1/3 deep.

[Stuck in NH]

sorry for the short repy, but i'm using the osk..

Is anybody worried about the amount of runoff [presumeably from the street] that the stormdrain suggests is at the bottom of that proposed wall?

-Stuck

[Lanelle]

Also, is that a well head in the first picture?

[Drafto]

Yes it is a well head in the first picture, I figure it goes straight down and I am not covering it, it will be built into my plantings.

The water runoff from the street, in the 2 bad storms we have had recently, goes to the other side. I have not seen any gushing or running water, and the customer has lead me to believe it is not a river like it appears it could be.