Friday, April 29, 2016

Happy Geese Season Means Swales!

It's 'Happy Geese Season' here at Cwm Goch (you probably know it as Autumn) and this past week has given us an abundance of beautiful rain with surprisingly mild temperatures. So despite being rundown with a bug, I managed to get out with younger munchkin and together we quickly built a small swale to catch the significant amount of water which was collecting down the drive.

A swale is basically a ditch which you would dig on contour in order to catch the water and hold it,  instead of allowing it to run off. I won't go into much detail because I've posted about this before. If you aren't familiar with swales there is a lot of good info here: How to build a swale on contour successfully -
Suffice to say, our aim was to help the water gathering in large pools to wash down where we wanted it to go.

To do this, ditches were made going down the hill (making it easier for the water to flow downhill where it naturally wanted to go) and then a swale was dug across the hill on contour to catch that water in a location we wanted it to stay.  See pics.

 This photo was taken from the high point (the large driveway puddles are behind me). You can see we've guided 2 streams in to join at a fork and continue down hill. When it was raining hard, the water was moving through this very swiftly.
The joined ditch moves on another couple of metres (6ft) and parts in front of the netted plum tree you can see in the centre of the photo. We deliberately made the downhill ditches very skinny to reduce absorption and therefore loss. Then we reach a T-junction. The picture to the left shows how some of the water gathers to the right while some of it continues to the left, past this tree.

And that's because we wanted the bulk of the water to make it further down to our 2 citrus trees (a navel orange and mandarin - see right)

I wasn't brave (silly) enough to take the camera out in the pouring rain so I'm afraid you won't get a shot of the swales being full but you can see where it filled to by the darker silt marks.

A lot of water fell this week and it's reassuring to know that instead of running off to nowhere, we've caught it and it's now being stored underground right where our trees need it.
We dug a similar system at the top of our food forest, but the swale is a bigger, deeper pit. It's right at the top corner, so hopefully all the winter catchment will support some good spring growth as none of food forest trees in the top section get watered, ever. They are hardy varieties like pear, nectarine, mulberry, nashi pear, pomegranate and almond, which helps and whilst they had some water in their first 2 years, now they're on their own - with winter rainfall only. The hope is that as they grow their canopy will provide more shade, reducing evaporation and the area should become lush over time.

Will post pics of the big ditch filling up later in the season. Have a great week! Enjoy the rain if you're getting some. :)

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