Pond Boss Forums INTRO Questions & Observations Penetrating lake bottom for pier?

Hello Gentlemen:

I recently purchased some property on a 22 acre private lake. I would like to build a pier and have questions on what I should do.

The lake bottom consists of 6" of silt, and then a very hard bottom. I assume the bottom is clay and was put in to keep the lake from leaking.

Should I go ahead and penetrate the clay layer by driving 6" wood posts or perhaps 4" steel pipes for the pier supports? Or should I build some kind of flat structure that would just rest on the bottom?

Thanks in advance for your thoughts.

I had the same challenge when I built my pier. I was able to pound my posts into the ground pretty well. I used cedar posts and hit them with a sledge hammer. They were in the 8" width range. It has been about a year and I have not noticed any additional settling. I also had been told that you could drive a T-post into the bottom alongside the wooden post with a T-post driver and then clamp the wooden post to the T-post. I decided not to do that.

If you were going to use 4" steel pipes I think that they would continue to sink under the weight of your pier. If they were to support a floating pier that wouldn't matter, but if a fixed wooden pier I think it would eventually cause problems.

Thanks for the insight. I am leaning to using wood poles over steel.... I think you are right that the steel pipe may continue settling.

My real worry is whether penetrating the clay layer is a no-no and will cause the lake to leak too much. Is the clay layer some sacred substance that should be left pristine? I would also like to drive a few smaller poles here and there so I can tie the boat to them while fishing with the wind blowing.

I am guessing that a few 6" wooden poles driven in through the clay layer would not make any difference on leakage, again considering that this is a 22 acre lake. But, before I did that, I just want to get more thoughts on the matter so I can be sure.

Thanks!

Gary:

Welcome to the forum!

While a layer of clay is sometimes applied to a pond bottom to seal it, more often no special attention has to be paid to the bottom (the dam is another matter). I suspect that this particular practice was NOT utilized for a BOW as big as 22 acres, and that the bottom clay is naturally occurring. That IS just a semi-educated guess. If you can get details of the original construction, you would know for sure.

Theo, thank you for the welcome.

This lake is about 20 miles south of Houston, Texas, and the soil make-up in this area is definitely clay. So the lake bottom may certainly be the original soil.

With that said, is there any reason not to set 6" wood poles into that clay layer?

The lake is about 7 years old, and the subdivision is hardly populated at all. Just a few houses here and there, and no one else has built a pier yet.

Most probably not.

Thank you Sir. I shall proceed with the pier!

Gary when I built my dock I used 4 inch 1/4 inch thick square tubing. It was easier to bolt the board to a flat side. Also I made a driver out of 5 inch square tubing so it would slip over the 4 inch pipe so I could drive it into the lake. Kind of like a tee post driver. Just a thought.

Hey John does the dock feel solid? Are you not worried about it sinking in the mud? I was thinking about doing it the way you mentioned but was worried that all the weight from the dock would just push the post futher and futher in the lake bottom.

JHFV We have put in 2 docks in the same way and both have not moved and inch. One was done 8 years ago and the other about 3. We just drove it down untill we couldn't drive it any further around 3 feet I think and then cut off the excess tubing.