Sand Dams the Permaculture Way 

Thank you James

Thank you...

Thank you...

Thank you. Gabion work is heavy graft...

Howzit... All the best with your project.

Sure, that can work, depending on the context of the river drainage line in relation to the terraces that will allow safe engineering. I was able to achieve this on another farm I lived on in the region 15 years ago but the setup was very different to this farm. The thing is that when you get these big flood rains there is so much water flowing off the slopes into the swales anyway and the production terraces get a huge soak. With rivers, often you can get more rain upstream so the river will pump down, even though there may not be that much rain locally, and that is when a diversion system will work. The sand dam then needs to be upstream from the swales or the terrace system, with a canal or pipe drifting off from the wall of the sand dam onto the terrace or swale system. Our context here does not allow for this, but it is possible in the right setup. If there is going to be a mega rainfall, then you can, close off the canal or pipe and open in smaller flooding events. There are so many possibilities with good design, it really takes good observation and then fine tuning after the system goes through a range of different events...

Thank you...

@@kenttahir.cooper5282 Thank you. 🙏🏼

А я противоположного мнения... Уважаемий афтарчика видеосика слишком много бла-бла-бла и никакой конкретики и никакого действия... Но ето поправимо ... При первом же проекте, он может поработать у меня общим работником и понабратся практическим опитом ... Далее его видеосики станут весьма короче и весьма полезнее обществу ...

Thank you...

For sure, observe and interact, the first principle of permaculture design and context is everything...

Howzit Kermit, shot man. I am working on another river training vid, this time on gabion groins...

Yes, especially in very hot dry environments where evapouration is a huge factor, which leads to salinisation of surface water...

Thank you... Yes most of the catchment is on our farm, however it is far too steep and wild to do any form of earthworks on, thin rocky soils, etc... In desert environments, flood surges are standard as vegetation cover is not dense. The best you can do is to encourage the growth of perennial grasses to provide as much land cover as possible, using livestock impact where possible. But at the end of the day the flood surges are just something you have to design for wherever you possibly can. In more gentle landscapes swales, riplines, berms, diversions, pocket ponds and earth imprinting will most definitely make a huge difference, as they will not only slow, spread, sink water but encourage denser vegetation cover, which is really the ultimate way of retaining run-off.

Howzit. I will be doing a new drone flyover vid in the next few weeks...

No. The river silt is not fertile, it is very sandy. My soils in the fields are extremely fertile loams. I manage soil fertility in place by integrated design between rotating livestock, legumes, subsoiling and effective guild formation. Moving around soils is not effective or possible on an agricultural scale.

The water surge is never a problem if the gabion walls are made in the correct manner and located well. The destructive forces of the water are always in the center of the stream course and start having impact where the river bends, as it starts to undercut the banks. I am busy with a video on gabion groyns, which addresses this issue.

Hi... Good question... It all depends on how high your stream banks are. If they are really high from the silt field then you can add another row of gabions, as you do not want the river breaking its banks. You need to step them back so you do not create a sheer wall, which will cause high water impact at the base of the wall and it could undermine it. Only make the sand dam as high as your stream banks will allow...

Its in South Africa, in a semi-desert called the Little Karoo...

@@kenttahir.cooper5282 thanks for your answer and by the way brilliant video

If you have coarse sand it will hold more water as there will be more pore space between grains. The smaller the grain, the more compact the medium will be. River sediment is a mix of all sorts of media, some with lots of clay, others with gravel type media and others with silt/sands...

@@kenttahir.cooper5282 It depends on the sorting of the grains. The size is irrelevant. A box of ping pong balls has the exact same ratio of pore space as a box of soccer balls. A box of mixed soccer and ping pong balls will have less pore space.

@@stevesavage8784 Thais fine Steve, I have no problem disagreeing with you. You are never going to get the same size grains in any river, they will always be mixed and never be spherical. However a general larger and courser gravel will hold more water, I have seen this directly with my sand filter systems on our natural pool. The really finer grain materials hold less water, are compact and have less pore space. This is a direct observation... Courser material will also drain/infiltrate quicker to the clay or rock base of the river, while finer material with higher clay/silt content will run-off more before infiltrating, however will retain moisture for longer if there is not impermeable base to the system. Context is everything.

@@kenttahir.cooper5282 Physics and geometry have their own context. Take some measurements. Sand filters are washed and sorted sands, so they will hold maximum water, but fine sands or coarse sands will hold an identical amount. Sorting not grain size determines water holding capacity.