Q&A: When Rainfall Is Adequate for Not Using Swales 

We live in a brittle environment, where rainfall comes all at once, with long dry spells in between. Average approx 660mms per year. Some years the swales are filled a lot, other years, they may be lucky to fill, once. We have found swales invaluable in their design, by reducing soil erosion between the wet and dry events. Because if your soil is dry, there is very little growing to hold the soil in place. Especially for pasture systems. Trees will hold a chunk of soil together, but soil can be eroded around their roots too. So as soon as you get that first, massive rain event, your soil is liable to erode. Rather than focusing on whether swales act as a water holding design element, only, consider how the rain falls across your land. If the pattern is for less rain events, with more rain falling (which seems to be the case around the globe) swales act as an erosion barrier, when there isn't enough rain to keep the ground-cover alive, between the wet and dry. Especially important, if you live on slopes, as we do. Swales aid in reducing soil erosion. We tried planting vetiver grass, as a soil erosion prevention tool, but just didn't have enough regular moisture, for them to do well. Swales became that permanent feature in the landscape, non-dependent on rainfall, to stay in place.

I love listening to Jeoff Lawton! He's a walking encyclopaedia of natural systems, all based on first hand experience. We can only learn through practice, of course some rudimentary theory helps but first hand experience is the best because it contains trials and errors. I love you Jeoff! Thank you for you great contribution to humanity! 💖😊😁😀🤗☺️😄

Even areas "with adequate rainfall" experience drought. The worst assumption is to assume there will always be adequate water.

Great question and answer

The Permaculture Earthworks Handbook: How to Design and Build Swales, Dams, Ponds, and other Water Harvesting System is an excellent reference on this topic

Surely it depends on what you want to do with the land, how resilient or fragile it is, soil type, how steep/flat...? I thought the whole idea of permaculture was to observe and make decisions based on those observations... You can't just chuck an either/or type of question into the air like that and expect an answer without knowing the detail.

Awesome video cleared up some confusion for me thank you Geoff!

You are brilliant sir.

Just like Geoff said, he uses both designs. Sure, Geoff is THE Swale guy, but keyline was developed in Australia, and is a major contributor to permaculture development. I truly believe they go hand in hand, swales and keyline, as different tools in a permaculturist's tool belt. Additionally, keyline is definitely it's own methodology compared to swales that are more of a landscape feature with some guiding principles

yeomans or keylines and keypoints is about absorbtion over a vast landscape by slowing down the water runoff and making it take a more circuitous passage over the land via the keylines and then saving it in keypoint dams/ponds. the ponds can be swales, deep swales. the idea being you use wind or solar to power pumps to send the water to the top of the system whenever you need water. the ploughing with their yeomans plough is not necessary.

The question to ask yourself is will adding extra water to my land cause problems for the soil, This will depend on things like gradient ,soil type, bed rock and your system. Other considerations are local water extraction pressures and up slope systems operated by neighbours. Monthly rainfall averages are probably more important than the annual rainfall average

Hey Geoff love the Channel, Richard Just did a Video on some of the negative elements of permaculture, I’m wondering your thoughts on this Video and could you make a Response Video ! Thanks mate !

It seems like Swales are most helpful in arid climates where rainfall is less than 20 inches per year. This person's rainfall is 46 inches per year. That's plenty of precipitation to get trees growing without swales. With 20 inches or less it is much more difficult to grow a forest and that's where swales shine.

It might be a question of property size. Key line design is easier on a small plot of land.

Hi! I have been studying Swales and Key line since one year back. And even when both are quite similar due to all contour , levels or Keypoint. Is not enough clear to me, when to use one or the other. In your experience, which is cheaper or easier to implement. Could you explain further like a Vs. Thanks for all your knowledge. Hope I can meet you one day, I wont be able to make it in Florida this month :(

Greetings Geoff I am from South Africa at warmer zones .I want to ask a question. I want to use Nitrogen fixers from my village . How will I know that some plants are Nitrogen fixers ?

So keylines are better for pasture land? I have about 14,000 acres I might be able to manage in the drier part of the Midwest of US and it is quite topographical with rolling hills, loamy soils, almost treeless outside of 100 ft from any ditch or stream. Would swales be good for slowing the water and letting it swell into the ground but that same ground cattle will be running on to graze?

I wonder if in degraded lands that are being grazed if it would be beneficial to do contoured Yeoman's or keyline for a year or two with cover crops before starting Earthworks? You could continue grazing the areas in between swales as well in the agroforestry manner. I live in Texas and when I have a say at our property which is just a typical ranch with a few hundred head of cattle, I want to implement positive change without financially risking the property in anyway.

Query: I am from India, Darjeeling Hills. The average annual rainfall of Darjeeling District is 2,812.2 mm from April to October. Kindly suggest how to manage the cultivation in this type of climate. My area is a Terrace Field.

If it doesn't piss hard when it rains then Swales not as effective

Dear Jeff Lawton, a bit off on a tangent, but what do you think about using something like the AR Sandbox, ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-bA4uvkAStPc.html, for planning/teaching this aspect of Permaculture? What I have in mind is using drones to capture good terrain/contour models for real sites, and then use the AR sandbox to a) rebuild the landscape in the sandbox (humans do the building, computer shows where to add/remove more sand until sand model matches the data), b) simulate realistic rainfall events and how water harvesting structures would function. I know you do not need the sandbox for this, you can do it on paper or screen or in your head/intuition. But I wonder if this tool would make it easier to communicate ideas to clients & students. I'm a tech geek with a desire to add something useful to the permaculture community, so let me know what you think about this. Thanks!

CRICKY