Retaining wall and leveling project:

[Kodthree]

Friends,

I need advise, guidance, and tips and tricks on a project in the "just thinkin' 'bout it" stage right now. Here is a picture of the project area:



Our lodge is built on the man-made dike of our lake, and about thirty feet back from the water. Our problem is that the dike slopes steeply away from the front of the structure to the water's edge, and as such is quite difficult to use and/or drive on most of the year. The excavated material from the lake forms the dike, and is clay, so it gets slippery and soft with rain or melted snow.
The general idea of this project is to create an arc'd retaining wall with its top level being at or slightly lower than the foundation of the lodge. The radius of the arc would be centered with the peak of the roofline. I think some stone or brick steps leading down to the water and possibly a floating dock projecting out from the area in front of the deck on the right side of the picture would be desireable, too. We intend to extend the driveway (with geo fabric, 3", and 3/4 minus) from the left of the picture to past the lodge on the right, adjacent to the structure, so it will be more accessible at all times, and we will cover the remainder of the back-filled area with grass to make a front yard, including a firepit area.
My questions are:
1: What is the cheapest and easiest material to use for a retaining wall (large rocks, basalt columns, gabiens, driven posts with treated timbers forming the wall, etc.)?
2: Drainage considerations?
3: Can a guy (that's me in this story) simply excavate a flat shelf along the intended area of the retaining wall, set the materials (rock, gabiens, or whatever) on that shelf or step and then just backfill, or is some kind of anchor used? To be clear, once constructed, nothing heavier than about 10 people will be anywhere near the edge of the retaining wall...it will not be driven on in that area at all.

Please feel free to chime in with any thoughts or tips you might have. I can include more pictures to help visualize, too. And, we'd like to do this in house as much as possible. I'm sure we'll rent an excavator for a lot of the work, but think we'll also need a rolling compactor over the back filled areas.

Thanks,

Kodthree

 

[Western]

I have seen telephone poles used exactly for what your talking about, but have no clue on the longevity. I would have concerns about a rock wall since you will really need one heck of a foundation. I know there are company's that contract both. I think driven in poles would be the easiest since you have water in the pond already. I know this isn't "how to do it advice" but it is 2 options I have personally seen. Might also be cheaper and easier to pour something like a stem wall and just top that with native stone.

 

[forgeblast]

Just wondering if you need to contact anyone before you mess with a water source? I am not sure of the laws/regulations in idaho. Pondboss is a website that many people have recommended over the years for projects involving lots of water.

 

[samandmax]

how about steel I beams pile driven down,figure twice the length in ground as above, spaced apart to slide 6x6's in the channels.

 

[Kodthree]

I like the pole idea, but have concerns about polution from the creosote affecting our lake and wildlilfe. The stem wall approach is a great idea, but probably more not the look (from the lake) we'd be interested in...face it with something? We have zero need to worry or plan for wave action against the wall...biggest waves in our lake are from the moose swimming by.

 

[Kodthree]

another great idea...what equipment to drive the beams, and how long will the treated 6x6s last?

 

[Kodthree]

Just wondering if you need to contact anyone before you mess with a water source? I am not sure of the laws/regulations in idaho. Pondboss is a website that many people have recommended over the years for projects involving lots of water.

Nope, its our water...all of it. I'll research Pondboss right now, though! Thanks.

 

[Tollster]

I have done free standing stone walls with field stone with various levels of success.
This one is around 2'-3' tall and 2'wide, backfilled with gravel to the edge,transitioned at a 45 degree angle for drainage off the hill,it has not pushed out after 4 years.

This one is about 4' in the highest placeand 2-3'foot wide,it pushes in the highest area, but its also on a hillside,I use the bota to push it back with 2"X12"'s across the bucket to spead the load.

Here is that whole write up on the construction,but most of it applies to the rock garden

http://www.tractorbynet.com/forums/projects/102305-pennsylvania-stone-wall-project.html

I have had better success with versa lock(solid man made blocks using nylon interlocking pins),but engineering is needed after 48"of height due to the hydrolic load that will push. Mine are no higher than 45" and have had no issues since 93-1994 or so.

With lumber,you have to be sure to get the ones "treated for in ground contact" and deadmans are required. I chose to use deadmans and .50" rebar for anything over 2 ters high as I only wanna do it once, 2nd time round is always more than twice the work!

Prices vary,but if you look hard enough,you will find a good price. My two stone walls are over 120'long for each,and have a total of 120,000 lbs of rock, 39 3000lbs pallets. They cost under 4500.99 for all labor,and stones,including backfill gravel. I did as much as i could though,plantings,layout,trench cut, and all loader work. It took 2 months minimum and looks great 4 years later. All leveling was done by sight.

HINT: Use a garden hose to get the curves you want,keep radiuses with in the turning radius of your mower, once you have the hose where ya want it,spray a line with marker paint along the hose, then use a flat spaid to cut the leading edge into your sod for a clean line.On these,I went 2-3" deep, then used my back hoe,leveled up with the outriggers to cut the 2' trench without the teeth on the bucket, all this then went behind the wall for fill as I moved along.

 

[Western]

I like the pole idea, but have concerns about polution from the creosote affecting our lake and wildlilfe. The stem wall approach is a great idea, but probably more not the look (from the lake) we'd be interested in...face it with something? We have zero need to worry or plan for wave action against the wall...biggest waves in our lake are from the moose swimming by.

Add a concrete colorant to the mix, or rather have the cement company do it. A light Brown to Dark Brown may accent your house (nice place BTW), Topped with a row of your native rock, might just "fit right in" .

 

[TCJatko]

If you have them, rocks from your place would be cheapest. How's that for a masterful grasp of the obvious? A small excavator with a thumb can do a fine job of placing or stacking the rocks; use geotextile fabric and a little gravel behind. Done all the time here in New Hampshire; they don't call it "the Granite State" for no reason.