Bootstrap @ Rippling Waters – Swales:

Last month I gave a few examples of how we battled with the elements all season here at Rippling Waters. I am going to keep with this theme and wrap up the remaining challenges I faced here in Southern Maine and how we are going about fixing them.

The earth challenge, the soil challenge; everyone’s soil seems to give them one issue or another, if it isn’t the structure it’s the weed bank, if it isn’t that it’s the calcium levels or the acidity, each issue as important and daunting as the next. Our biggest issue is a sandy soil, so sandy that if you dig down a foot you will pull up a golden stretch of beach. This soil does not hold things, whether they be water or the nutrients that are carried with it. Even without surface erosion from rainfall, sandy soils deteriorate physically and chemically as lenses of water slide downhill beneath our feet. A slope can quickly become a wash and without some mitigation you end up with a desert on a hillside.

Swale diagramThat is more or less what we have been observing over the last two years in one of our main upper plots. This year we forewent planting it and headed to the drawing board to fix the problem once and for all. We were particularly interested in an ancient Eastern practice of water mitigation where farmers create massive trenches, or swales, along the contour of the hillside. The biggest enemy is fast moving water, so if we can slow it and sink it into the landscape using a series of trenches that span the hillside and obey the various changes in pitch or rise, then we can prevent erosion and nutrient loss.

The extreme of this technique would be terracing, a practice commonly used in rice paddy farming where farmers dig ponds into the hillside that collect water as it rolls down the hill. Terracing is an ingenuous way to create microclimates as well, allowing mountainsides to harbor a variety of vegetation and biota which may be unprecedented on that spot. For more on a really unique and genius terracing system check out the work of Sepp Holzer, who has carved out a permaculture paradise in the frozen Lindau mountains of Austria.

Swales are less labor intensive and serve more in slowing the water moving down a hillside rather than trapping it indefinitely. To begin we needed to find the contour lines along the hillside we were choosing, which are essentially created by finding a series of points across the hill that are at the same elevation. This line curves much like the lines you see on a topographical map, and indicate the very rise and fall of the land.

A-Frame LevelTo find this we constructed a very low-tech, easy to build tool called an “A-Frame Level.” I took two five-foot poles and crossed them at the top like a tee-pee and then screwed in a cross brace about 3 feet off the ground (forming the letter A) – it is important that the distance from the cross brace to the ground is equal on both legs.

Next, using a level surface, I took a heavy rocky and tied it to a string and then tied that string to the crux where the two main uprights met, long enough so that it dangled down below the cross brace. Holding the whole thing upright I drew a vertical line where the string came to rest, flipped the level so the feet exchanged positions and drew another line. That field informs us of when the two legs are on ground of the same elevation.

From there it was a matter of tracking across the hillside, flipping the frame horizontally and always holding the trailing foot of the level in place to get an accurate contour from one side of the hill to the other. We used stakes to mark the trail and then got to digging.
To dig the swale we pulled with hoes from a foot uphill of the line downhill into a lengthy berm. The resulting channel, or swale, is what we really want but because we are concerned with growing food we souped up the berm with compost, manure, and seaweed and mulched it so next year it will act as a planting bed. This serves also to hedge our beds against erosion: even if the swales don’t prevent runoff, the height of the berm will ensure a long-lasting growing area.  We did this 7 times down the hill, cutting the swales about a foot deep and a foot wide to double as paths for future farmers.

Swales at Rippling WatersAlready we have seen water pooling in the swales and have even planted some of them with perennial herbs in accordance with our permaculture transformation of this plot for next year. We hope to add in an Asian Pear tree for shade and fruit surrounded by comfrey and yarrow that will help pull nutrients and minerals from deep in the soil on up. We will plant Siberian Pea Shrubs in this plot to help increase overall fertility as their roots, like those of other legumes, are fixated with nitrogen clusters by bacteria in the soil. The shrub is also another shade plant, helping us to grow cool weather crops in micro-climates throughout the summer and thereby increasing our overall diversity and profit.

Water mitigation is a vast and important topic within farming. Soil and water are inseparable in terms of how we think of them, and there are various grants out there from the Natural Resources Conservation Service that can help you tailor your land to better handle water moving through the landscape. A few years ago they helped us dig a massive gully in the middle of our farm and line it with rocks, greatly increasing the ability of our land to dry out in wet times.

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