has anybody had any luck jetting in dock pilings using a preasure washer? The area where I intend to buld is a soft sandy/muddy bottom. Does anybody have any pointers?
this is probably a job for a professional unless you only plan to put the piling down a couple feet. If you live anywhere where the water freezes, ice will literally lift the piling up.
My boat is in water about 8 foot deep and the piling are driven down maybe 15 to 20 feet below the lake bottom. With the overall length of the piling 25 to 30 feet, just picking the thing up is a major job. The marine contractor did jet the piles for the part of the way down so that theory is right. The problem is having equipment big enough to handle the pole, hold it upright and have enough volume of water to jet it down.
Once jetting set the pole halfway, the crane used a whammer to knock it down the rest of the way. The crane, barge to float it and large pump to use for the jet, aren't the kind of typical homeowner tools. Here, they get about $500 to stick a piling down. That includes the cost of a piling (used but good shape) and the labor/equipment.
I did not use a pressure washer, but here on Lake Murray, SC, I did jet some 6X6 Pressure Treated Pilings into RED CLAY. I hooked up some 1 black plastic pipe to 1 PVC Pipe, to a brass fire hose nozzle (about 1/8 outlet). All of this was connected to my irrigation pump on the pier and used water out of the lake.
I was able to Jet-in the 6X6's to about 3-4 feet, but had to make a rock-buster for a couple of the rocks I encountered. Basically we used a 10' section of PVC pipe and just bounced it off the bottom until we had a hole as deep as we wanted. KEEP IN MIND, MOST OF THIS WAS RED CLAY! So I was pretty impressed with the results.
Now, three years later, the posts have not moved a 1/4 in any direction. But the lake does not ever hard freeze!
Hope this helps, if you need more info, let me know.
Tags: dock, pilings, piling down
