Our land is half gully and half sunny hillside. This makes it quite versatile, as the gully stays wet and lush, while the sunny hillside stays warm and dry. This is important in the winter, because the animals needs a dry place to live. However, most of the year, it's a little too dry.
Every season, there is at least one rain event that turns our gully into a rushing river. Rain runoff streams down our hills, carrying sediment and nutrients down to the gully, where it goes away in a great torrent.
Wouldn't it be great if we could catch that, and save it? If we could store the water in a high holding pond, and distribute it evenly across the land, surely it would improve our soil fertility.
Water harvesting has been done for ages. The advent of the diesel-powered earth-mover (or digger) just made it easier. In May of 2011, we hired a digger and a driver for a week, to create a hillside pond, fed by a system of swales. Swales are just ditches that run across the hillside, built dead-level to allow water to accumulate in them, spreading evenly across the land.
The main advantage of using swales rather than pipes and sprinklers is that swales help to collect water, as well as distribute it. The area around each swale becomes very fertile, suitable for planting trees and bushes, creating shelterbelts that provide shade and wind protection, which in turn increase fertility even more. Swales do not require any pumps or maintenance (more on this later).
On the first day, the digger began to build the pond. The pond was created by building a dam about 35 meters across, holding roughly a half-million litres of water. He removed the valuable topsoil, saving it for later.
Beneath the topsoil is the subsoil, which in our case looks like clay. The digger started to dig the shape of the pond into the subsoil, and had to quit for the day.
It started to rain.
It didn't stop for five days. The subsoil became a slippery, sloppy mess. It would be impossible to work until the whole site dried out.
Three weeks later, we returned to the project and finished it. It was a lot of hard work, and it was pretty expensive, but it was worth it.
A few months later, another rainstorm came and filled the pond. Hooray! We went out and bought a truckload of water lilies and some fish in a little baggie. We were carrying the fish up to the pond, when we stopped dead in our tracks. The pond was empty! There was a hole in the bottom of the pond, straight down into the clay subsoil!
After getting pissed, and eventually recovering, we decided to talk to an engineer. He came to look at the dead pond, picked up a handful of subsoil and squeezed it between his fingers. "Aw, this isn't clay. It's loess. Loess looks like clay when it's dry, but it's bloody useless when it's wet."
Our already expensive little pond just got a lot more expensive. We had the digger come back in January. He reshaped the pond and installed a clay lining, which we had trucked in from a nearby quarry. Then we rolled the clay to compact it, and spread river rock along the bank.
If this didn't work, we thought, we would be the proud owners of the most beautiful hole in the ground in town.
We prayed for rain.
The pond has been full for several months now, and so far, all is well. The ducks have taken to it, and it has attracted a lot of wildlife. The number and variety of birds that we had this year was staggering! We have started to plant trees and bushes around it, now that we know that it won't need another dose of digging.
The rainstorms that came this year filled our swales pretty well. Unfortunately, our top swale developed a series of holes in it, probably due to rabbit holes and under-runners (subterranean caverns caused by runoff). We patched the holes as best we could, but more holes would just open up during the next rain. Eventually, we resorted to installing a clay liner, similar to what we did in the pond.
Last month, we had another of those big rain events. All three of our swales were full, and the overflow was feeding right into our pond, filing it up to the brim. We actually had to go out with spades and shovels during the middle of the rainstorm, because the pond was in danger of overflowing the dam. There was an overflow channel to divert water away from the dam, but it wasn't deep enough. We managed to avert disaster, just as the water was beginning to overflow.
The following night, I had a nightmare. I woke up screaming, and as Gail and I lay there in bed, we felt the earth tremble. An earthquake! Gail shot out of bed and turned on the radio. There was no news of anything unusual. The next morning, we checked the online seismic drums. No earthquake. But we had both felt it....
There was a break in the rain, so I went out to see how the lining in the top swale was holding. Not good. There was a huge hole in it, and all the water that had been there the previous night was gone!
But that's not all. As I traced the water's path down under the hillside, I saw enormous holes in our pasture, where caverns had formed and collapsed.
The collapsed caverns made a line straight down the hill, to an access road that overlooks the gully. There had previously been a little erosion on this access road before, and we had erected a small retaining wall. The amount of erosion that happened the previous night makes that retaining wall look like a box of toothpicks. This was the source of the earthquake!
I don't know if I can describe the feeling I experienced when I saw this. Detachment. Resignation. Acceptance. Zen. In the following days, we planted a hundred trees around the site to stabilize the erosion. There's not much else we can do.
Other than that, life is still pretty good. There are occasional dramas, of course, but on the whole, we have enough beauty and serenity in our lives to keep us happy.
Levi is as big as a horse!
Kayla graduated from university, which was a huge celebration for us all! Her degree is in media studies, and she is looking forward to a career in media production. She is so awesome! Hire her. Now.
There is still a lot of news left to tell, but that's all the time we have for now.
Thanks for reading. Best wishes to all,
--zim
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