Water Infrastructure

Rainwater Harvesting Swale

This project was seeded 3 or 4 years ago. I think it was early spring, following a wet but warm winter. This means that snow melted quickly and saturated the soils. So that when spring rains came there was a lot of runoff. This effect was amplified greatly by the almost bare surfaces of the rest of the valley due to over-grazing (leaving the land bare and increasing runoff).

For the first time at Bhudeva I witnessed for almost 48 hours a strong current of water flowing past our land, onto the road (eroding a large ditch in it!) that leads down to flatlands at the entrace to the valley (where there was once, I’ve been told, a lake). It was heart-aching to watch all that precious water flow away. But I watched closely: I watched where the water was coming from and where it was accumulating and I hatched a plan. At the time I only placed on the ground some scrap wood to mark a certain place … the rest took a few years to manifest.

Sidenote: I often do this: when facing a project that I don’t know how to tackle, I look for something small to do, a gesture of intention and an invitation for a project to come into being.

Actual work started last summer when the Belgian Scouts visited us and took on the task of moving the large pile of scrap wood behind the barn and to form it into a kind of hugelkultur raised bed. I guided the shape from the point of origin (I had marked in my small gesture) and all the way to where it would end and outlet. It was a bit counter-intuitive because it was not on contour.

A few months later, when we hired the excavator for finishing the Earthbag Cellar, we also did the swale excavation and burial of the raised bed. At the beginning of the swale is a small catchment basin (situated to catch most of the water that comes from the land above us where the sheep graze):

Then the rest of the swale started as an overflow from that catchment hole:

The swale goes all the way around our well and drains into a field. The bottom of the swale is flat-ish and it has, near the end, a small damn (a hump of soil basically) that keeps a certain level of water in the swale. If the water accumulates in the swale and rises above the level of the “damn” it overflows into the end of the swale and drains into the field.

… and that was that … I forgot about it … until early spring when I started my morning visits to the Linden tree

I walk past the well and suddenly the ground under my feet feels unusually soft … I look around and see this:

I’d forgotten about the swale … so for a few seconds I was wondering what happened here. Then my eyes start to look up and around and I realize that a delta-like pattern had formed at the end of the swale … which meant that there had recently been a good flow of water came out of it. It worked! I walked around to the collection end of the swale and saw clear evidence that water had pooled there recently:

Now, whenever it rained I started paying closer attention. Sure enough in the following weeks I went out, sometime (an hour or two!?) after rain stopped and I found this:

Textbook performance. The water is captured, slowed down and given space to meander on our land. It has time to soak into the soil and its overflow continues into our field where it continues to soak into the soil and in the future can be directed toward gardening in that area.

Back when this story started, when a continuous current of water flowed down our road, I recall the enchanting sound of water flowing (we do not have running water around us). That is why I felt delighted, when, AFTER the rain had stopped, I stood next to the catchment basin and heard water flowing in:

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