Jet washing pilings

Don in LA

New member
I just noticed that "ilings" should have been "pilings". Ooops. I wasn't able to edit that.

Hey guys. My son and I need to set pilings in my canal out to the river for a boardwalk and boat slip at the river. I think the most efficient method for a DYI project is to jet wash the pilings. I think I have the basics down but I would appreciate any tricks and tips. The canal depth ranges from almost dry to an average depth of about two feet. During floods from hurricanes, etc. it can get to eight ft. in depth or more. I think I can use 4X4's or 4X6's for the piles. The canal bottom is mostly fine sand. It seems that once piles are set more than a couple of feet the suction holds them in pretty good but I want to make sure the boardwalk and slip don't float up during floods. To be practical, I plan on setting the height of the boardwalk at about two feet above the normal "high water" level. That would mean that during high floods (once every year or two) the boardwalk would be about three to four feet under water. I think I will be OK with setting the piles four to six ft. in the bottom. We have a 300 GPM gasoline powered pump and a small homemade barge to work with.

Anyway, I would appreciate and suggestions on the jet washing technique and proper height to set the boardwalk and piles.

Thanks.
 

bczoom

Senior Member
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Can't help with the jetting.

Just wondering if floating the boardwalk is an option. You set your pilings but the decking of the boardwalk is on a floating material (e.g. empty 55 gallon drums) so the deck floats and always sits just over the water.
 

Doc

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Those of us within 6 or so miles above a damn on the Ohio can put in what we call permanent docks. Water level does indeed fluctuate but usually in the summer it is withing a couple feet of normal so the docks work fine for our boats. We normally flood in the spring and yep, the docks will spend some time underwater. No problem. I've had my original ones in for 15 years with no issues. They do not go underwater every year, but it seems to go in streaks. We will get hit a few years in a row, multiple times a year and then we might have a few years off. Going underwater does not seem to have any dire affect on the docks.

I know nothing about jetting, or how you could do that.

We use what we call Big Bertha to drive the posts in. I can get a pic for you if you want but this is the easiest method I've found to get the job done. Picture a 36" piece of pipe, 6 inch OD. Welded at one end with a hunk of steel in the top where it's welded and two handles coming out either side. It weights 60 to 75 pounds I'd guess. We named her Bertha and she has worked me and my brothers pretty hard on many occasions. She has also worked many of our friends and neighbors as they saw how well it worked and wanted to put in their docks like ours.

We would use treated 4x4's. Lets say we want to be 2 feet above the normal water height. and the water is two feet deep or less. You could go with an eight ft 4x4 and still have 4 ft in the water. 4 ft is the minimum we go for. Sometimes we'll go 5 or 6 ft in the water. We use 8ft, 10ft and 12 ft 4x4's to get the job done as we deal with varying depths as the docks extend out into the river. Just slip Bertha over the top of the 4x4, stand her and the 4x4 up straight (yeah we use a level and one man below holding and twisting the post if needed to keep it close to square) and lift and drop Bertha onto the post. She drives em in darn good. We deal with Ohio River mud more than sand but I would guess once you are four ft or more in the posts will stay just fine. And after you add the framing that sturdies up all the boards. Works like charm.

Then we frame with 2x6's and have found that 2x6's for the top deck work best and do not cost much more than decking boards. Decking boards just do not last. We made this last set 6ft wide and ran two support runners up the middle as well as the two outside framing boards.

Sounds like a neat project you have going. I'm hoping for pics. :D
 

bordercollie

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Doc, that is great information! Big bertha sounds a bit like a giant version of my T post driver but in reverse- the post driver is a lot smaller and weighs about 20 lbs. :a1: I'm gonna store this info away. bordercollie
 

Doc

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Doc, that is great information! Big bertha sounds a bit like a giant version of my T post driver but in reverse- the post driver is a lot smaller and weighs about 20 lbs. :a1: I'm gonna store this info away. bordercollie
Yep, it is exactly like the much smaller T post drivers ....just bigger and heavier. I didn't mention this above but driving posts with Bertha is a three man (or woman) job. One on each of the T handles and one below keeping the post straight and ensuring that it does not twist. In the event of a twist (which happens semi regularly) we use a BIG pipe wrench to twist the post back as the other two folks are lightly pounding with Bertha (short light strokes). All in unison. All I can say is it works. :)
 

Don in LA

New member
Thanks for the info. I'm still not sure what method I'll be using. I will have to put in about 100 piles. My son has done some small jetting projects but I haven't. Basically, it is pumping water through a 3/4" pipe to the base of the pile and the water jet displaces the sand/mud and the pile sinks pretty quickly. Then remove the water jet pipe and the pile stays in place. It'll be a while before we get started but I will send pictures.

Don
 

Doc

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Sounds interesting. Doing it the 'Bertha' way or the jet way ...no matter 100 piles will take some effort. We would build a dock with 32' arms and a ramp and 12' connector walkway and use 60 to 70 piles. We could get er done in a 3 day weekend but we'd sure be sore afterwards. For the taller piles we would use ladders on the floating docks we used as a base. This would allow us to get Bertha up on the 12 footers. We even did 16 footers one time but it was simply to deep for them to have enough in the water and do much good.

Good luck with your project.
 
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