I have just about finished the pier for my 1 acre pond. Before the water gets any higher I want to put in a small sandy beach beside the pier (about 25 feet x 30 feet). The sandy beach would be for small kids to use, and I also hope that bluegill might use it to bed where I can see them from the pier. The water level of most of the pond drops off suddenly to about two to three feet deep, but we left a small area next to the pier with a gradual slope. The picture below shows the water line in blue and the proposed sand in brown. I thought about building a slight berm (shown in red) to try to reduce the tendency of the sand to shift towards the deeper area. The area between the step ladder and the proposed berm is almost flat.



I would appreciate any thoughts some of you with experience may have. I have followed some of the previous beach threads, and I have several questions.

First, I had planned on using geotextile fabric as a base, such as has been described by others. But a friend the other day told me of a relative of his who built a sandy beach using soil cement as a base. I have used soil cement for other projects, but had not thought about it for this one. The idea would be to spread Portland cement over the area, incorporate it into the upper four inches or so with a rototiller, and then wet it down. The existing surface is mostly clay, which is not the best material for soil cement.

What do you think of this idea in general? If I go with this approach, does anyone have any recommendations for the thickness to spread the cement before incorporating it into the soil? I had figured on about a half inch thick, which would give about a 1 to 10 mixture. An inch would give about a 1 to 5 mixture.

As you can see from the picture, the water will soon get ahead of me, so I don't have a lot of time for testing or to consider the options. It looks like I will have about five days of sunny weather, so I probably need to get started ASAP.

Thanks,

Charlie

I can't comment on your beach plans but I like you your pier/gazeebo plans.

+1 looks nice!

I'd lean towards the geotextile, but only because I have zero experience with the concrete soil. i'd make sure that I have the berm across the whole area that I want the beach, and carry the geotextile fabric up and over the berm. It's shaping up nicely!

What about pouring a small concrete "lip" on the outer edge of the berm? If the sand slides it will hit the lip and have to go uphill.

Both would be ok Look at the price and then make the decision.
The sand will move down hill so anything you do to keep it in place will help.

That is kind of what I am planning to do in some areas. The first picture below shows the levels on the left and right side of the pier. The left side (where I want the sand) has a gradual slope. The right side has a more sudden transition to deeper water.

I had some old concrete driveway borders that I placed between the two areas to try to keep sand from moving across from the shallow area to the deeper area.

I plan to try to find some similar barriers to place on the opposite area. But I'm a little concerned about having concrete close to the pier where people might dive in. In that area I might try soil cement with some clay on top to make the surface a little softer.

Charlie, are you concerned that those barriers aren't going to be high enough? Or are you planning on digging down a foot or so in front of these barriers to add some depth to the sand?

One guy on our lake keeps his sand beach by taking those (this is a guess on the size) 6" x 12" white patio blocks placed side by side. Every couple of years he has to redo them, but we get a lot of wind and wave action here on this 10 acre lake. He is on the western shore, it works pretty good for him. Right where the water meets the sand. His sand is white, and you can't really tell that he has the white blocks there.

I had planned to dig out a little, but not a foot. Do you think it needs to be that deep to reduce the migration of the sand over the barriers? I was planning on making the barriers a little higher in the section towards the deeper water. I was also thinking about using concrete blocks to anchor the berm in that area (except for the portion closest to the dock).

It was suggested that way to me, to make it 18-24 inches deep everywhere. Might be ok if it's deeper in the deeper waters, but not as deep in the shallows.

Here in Norway we use shell sand when constructing beaches,
It dosent wash away as fast as traditional sand a layer of 6 inches on top of textile last aprox. 10 - 15 years.

http://www.boston-as.no/
http://www.sandstrand.no/sandstrand.html

The links are in norwegian but might be of help there is a video showing before and after.

Buy the way its the same product that is most commonly used here
as PH buffer to the watter

I like the idea of creating a bluegill bedding area right by the pier. Would make for some neat time to sit by and watch.

A friend of mine, who happens to be a civil engineer with lots of experience, has told me that he really doesn't think I need to use either geotextile fabric or soil cement under the sand. He thinks the hard clay base would support the sand by itself--so long as I have some sort of terraces or barriers to keep it from sliding down the slope to the deep areas. As I mentioned earlier, most of the area with the sand is almost flat. Only the area at the edge has a steeper slope, and that area is only about ten feet wide. Now I'm thinking about placing some concrete blocks to serve as a base for the berm, and then covering the blocks with soil cement to make the berm. Since the steeper edge covers a pretty small area, it would not be too big a deal if I had to add sand to that area every year or two. That would certainly be a lot less expensive.

Any suggestions?

I and others would have suggested concrete blocks if not for the almost guaranteed stitches someone will be getting. If Concrete blocks are used, make sure they are in at least 10 foot deep water or more to prevent a serious injury.

I decided to put the berm in the shallow wading area that will be delineated with a rope and floats. We dug a small trench, put in some soil cement, set the blocks in the trench, and then filled the holes and covered the blocks with soil cement.

I still haven't decided whether to use geotextile fabric or soil cement, or just rely on the clay to hold the sand.

I guess Hurricane Ida made this decision a moot point. This is what the beach site looked like Sunday. You can see the overflow pipe across the pond about two feet above the water level. I used concrete blocks filled with soil cement to make the berm, which extends out from the bank and then turns to join the other berm under the pier. The portion of the berm under the pier is just some old concrete driveway borders.


I had planned to rent an excavator this weekend to scoop out the beach area a little deeper, then rototill some Portland cement in to make a base of soil cement, and then start hauling sand. But the six inches of rain from Ida changed it overnight to look like this:

I guess I'll go ahead and haul in some sand and see how it all looks next summer. If necessary, I suppose I could lower the level then and do some more proper preparation.

I have been just one step ahead of the water through the whole project, but this time it finally got a little ahead of me.

For what it's worth, it looks very nice now.

Agree, it does look good. I can almost guarantee you it will get low enough next summer to get some more work done on the beach area.

Welcome to full pool, Charlie! The blessing, beyond the brim full tub, is that you shot good elevations on the gazebo deck.

Not one to trust modern technology, I used a water level consisting of an old red cooler sitting on top of a 5 gallon bucket and some blocks to adjust the height. I ran the hose from the cooler to the drain pipe to set the water level and then brought it back to the pier to mark the water level there and calibrate the transit. Ida not only filled the lake, but she also lifted the cooler and the bucket and deposited them across the pond.

That is hilarious Charlie.

Just go ahead and dump the sand in. That is what we do to replenish our sand. Works without problems. Back the truck up and dump it in as far as you can. Then shovel it around. Over time and with the help of kids it will wash or get moved in.

I wanna see some of the octagonal deck details.

I have a description and a layout on another thread at http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Number=185709#Post185709. The final design for the connecting pier is slightly different from the illustration. I'll try to add some more images there soon showing the framing and the assembly. I ordered a 12 foot gazebo kit and an 18 foot floor kit from Amish Country Gazebos. I had them slightly customize the floor for my application, because the kits are designed assuming the same diameter for gazebo and floor. I laid out each of the 6x6 support posts to be directly under the gazebo posts, which will give a three foot cantilevered deck outside the gazebo. I did it that way for two reasons: First, I wanted the load to be transmitted directly from the gazebo to the ground. Second, I wanted to hide the supports, so the floor would appear to float just above the water.

The floor kit comes as eight wedges, which arrive fully assembled except for the boards over the locations for the bolts connecting the wedges. I installed a larger post in the center, where the 8 wedges come together. I had them leave off the floor boards where the frame attaches to the supports. After placing the wedges on the posts, I drilled three holes through each of the pairs of connecting wedges and bolted them together. I also drilled through the 2x6 stringers and connected them to the posts with 10" lag bolts.