Today, more than a year after having installed our first major water harvesting earthworks at the Tikologo Permaculture Site, we can finally report that swales do indeed catch water!
Now this may sound strange as obviously swales and other earthworks catch water, that is what they are designed to do isn’t it? That is all very well but installing water harvesting earthworks during a major drought can definitely leave one feeling more than a little dissatisfied. That’s not to mention the serious design questioning that starts to occur when the systems don’t fill after a whole wet season.
The Groot Marico district along with the majority of Southern Africa has experienced 3 years of below average rainfall but finally these last couple of months have brought relief. Since the start of the wet season in October we have had more than 600mm of rain taking us to our regional average with a couple of months of rain still to go. The continuous rain has soaked our soils and yes, finally led to a proof of swale concept for the site.
When we designed and implemented our swales in October 2015 we based our sizing calculations on maximum rainfall events. Through various conversations with local neighbours it was confirmed that in the last 100 years our valley had experienced 2 instances of 200mm flash floods within a 24hr period. Although this was the maximum event it would have led to very large installations based on the size of the catchment area. Due to this we opted to cater for a more common occurrence of 100mm of rain in 24hrs. This still led to what at the time seemed like gigantic scars in our landscape but the project site experiences a semi-arid climate and long periods of drought hence we made the possibility of catching every single drop of rain a necessity.
I will discuss the design of the water harvesting systems for the Tikologo property in more detail in a follow up post but for now I feel that the most exciting thing to share are some photos of how Tikologo’s water harvesting swales have evolved. The latest photos were taken on 20 February 2017 after 60mm of rain.
I hope that these images bring hope to anyone feeling impatient or demotivated. A wonderful byproduct of working with nature is that we are forced to learn patience so hang in there and the results will come.
If you would love to start catching your own rain water using swales or other permaculture techniques join us at one of our training courses so that we can help you on your way. Check out our Facebook events page our website for more info on upcoming courses.
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