What I had was a large storage pond which collected runoff from its western uplands. The expectation was that it would recharge the collected water into the aquifer from which the windpump drew. The windpump delivered the lifted water into an overhead storage, from which I had laid pipelines all over the planted area.
Conceptually this system is flawed and no different from dams which gather water and distribute it via canals. The main action in this system is to collect runoff. The objective of a true watershed design however should be to *prevent* runoff and encourage recharge. My pond had a clayey bottom and so it probably lost more water by evaporation than due to recharge. Rest of the property remained dry and needed piped water. It’s not just more work; it’s also bad design- and therefore, my woes.
One can see this bad design in every centralised system- in every farm, government works and municipal systems. Entire urbanisation is based on centralised supply of water and power. Nature on the hand creates distributed systems, with millions of microstorages in ditches, leaf litter and aquifers. Nature further creates canopies to reduce evaporation. Clouds floating above do not rain on dams and rivers alone, but everywhere, increasing distribution. What I needed to do at pointReturn was to trap water all over the property and encourage it to percolate at the point of capture. With tens of places distributed all over for collecting and gravitating the water into the ground, I would be rehydrating the whole land [less work with pipelines] and awakening more underground pathways for water to flow to the pond [steady supply to the pond]. Differently put, the surface area of contact between collected water and the earth determines the quantity of recharge. Holding a million litres distributed over 10 acres will always beat 5 million litres held in one acre, given of course the porosity of the soil is the same. Again distributed bodies will even out the odds of impervious bottoms found in some of them.
Awareness of pointReturn’s situation and the needed course correction dawned on me as the hot months sizzled by and the pond drained . How do I implement RWH on multiple acres? The answer had lain in me waiting for the right question to be asked. It now popped up: swales.
I scrambled to revisit all the pages, notes, websites and videos I had idly browsed tossing this swale-thing about my mind. Now they all made immediate sense, quickening me to action. A swale is a means to percolate water into the ground rather than hold it, as a pond does. We will come to the sizing of swales a bit later, but for now a quick description: soil excavated to make the swale is piled on the downward edge on the slope. The mound is planted out successively with legume, cover and tree crops. Since a swale is located on contour line -meaning that its bottom is dead level- water entering the swale spreads throughout its length.