Need help with shoreline erosion on private site

[Boody]

Our lake was built in 2007. The soils is almost all clay. We are now starting to see the shore shelf in areas, causing backwash until the water fluctuates. The shores were 12 to 1, when the lake was new. Now its more like 4 to 1 on the top and 15 to 1 lower. So when the water drops its perfect. I am looking for the best type of rock to suite our needs. I dont' want to put anything on there that is going to wash away. I need something to stay in place and stop the erosion.

 

Thanks!

[RichardDoane]

The broho shore erodes when the lake gets way full. "Rip-Rap" is what they've been lining the north end with. Pretty big chunks, so it says in place. I'll look for a pic. and post

[RichardDoane]

Boody - go to the "baller's everywhere" discussion, and look at the island and shore in the background behind Dave. OF and Lee have been throwing rocks now for weeks.

[thompjs]

https://picasaweb.google.com/JimSThompson/Phase2#

 

The last few pictures show Bull Rock (similar to River Rock) about 3in size placed on 4oz Geotextile fabric. This does not move at all.

 

Depending on your soil type and rip rap size, not using a geotextile fabric may actually make the erosion worse.

 

Also there are some shots of using Geotextile and sackcrete bags to armor small turn islands.

 

Contact me at jim at lsfdev.com if you need more info

[Boody]

Thanks guys, pictures say a 1000 words

[eleeski]

Jim, too bad you put an island in your lake. It looks like you did a good job on erosion control on it so you'll be stuck with the stinkin island forever. I hate turn islands! Beautiful lake otherwise!

My lakes are solid clay and erode to a wall and shelf with nasty backwash resulting. Has anyone tried telephone poles or floating pipes to reduce the rollers? Transportation of the riprap or rock is prohibitive for my application.

Eric

[thompjs]

We planted Pampas Grass, which choke out all of the weeds and other plants. At least in our area it works. For slalom on our place it works out nice to have an up and around. The way the islands are offset to the same side allows trickers the full length of the lake for runs.

 

We have heavy clay as well. Often putting barriers near the shore causes more turbulence that increases the erosion. Some sort of system to break up the waves a few feet (5 to 10) away may be a solution.

 

We found the a dock post within a few feet of the shore will create more erosion right around it that the rest of untreated shoreline. When we redid our docks after the drain and muck out a few years ago we made sure we bridged out to the main dock and set the walkway posts about 2 feet up the bank.

 

 

 

 

[ral]

@eleeski, the good thing about turning islands is that it is impossible even for a bad driver to put waves into the course while turning...

 

A suggestion, make every skier in the lake to bring 10 lbs of stones/rock when they go for a set. In 2 to 50 years, depending on the number of skiers, you will have enough...

[jackski]

Anyone ever try any of this type of things? This is just one product.

http://www.armtec.com/en-ca/Products-and-Services/Soil-Retention/Geosynthetics/Geocell.aspx

[Old MS Accout]

RAL,

That is the only good thing about 30 inches of ice. We get to drive out to the turn islands with trucks.

[boarditup]

Rip rap will sink into the clay over time. You need to support it with some kind of a fabric. If you want the shore walkable, you can use a heavy woven or non-woven fabric, covered with a geo-cellular structure, and then filled with rock. That will have a 50-plus year life span and will assist in filtering some of the water as the clay settles into the void spaces. Rock about 1" is walkable and will stay in place even with wakeboard boats running by. You also can make an artificial sandbar of rock in about 2' of water depth to break up the rollers in both directions. That requires the least amount of materials, but looks funky to the average slalom skier. I will be using the design on my next lake project - too bad I cannot make money from a patent on the design.

 

Stone conveyors can move stone about 120' from the truck location. They are not expensive and can go wherever a concrete truck could travel.

 

Please let me know if you need details.

[thompjs]

Boarditup, you are right. For heavy clays use 4oz non woven geotextile fabric. Mirafi is one brand.

[mt17085]

@thompjs, Would you mind giving us an update 4 years later on how the rock and fabric are holding up? Any erosion? What slope was it put on? How thick was the layer of rock? Was the sacrete used only on the islands or along the shorelines as well? Thanks!