1.8 Acres in Maryland (III): Swales (April 2017)
(Originally written by The Biologist and posted at www.permies.com)
Our first swales!
If you look very carefully at some of the bamboo fence pictures from the previous post (like the one above), you can see a number of shorter bamboo stakes in the foreground. These were places on contour, measured with an A-frame level built out of an old 1x1 found under the side porch of the house. It was my kind of building - no precision cuts to worry about! It did take about two tries to calibrate it, but that wasn't so bad. We hung a trowel off the end as the weight, and it did not take long at all to measure contours for this small an area.
Once the stakes were all in, we hand dug small trenches and piled up the soil on the next line up the hill from the current trench. We used the A-frame again to make sure the bottom of the trenches were reasonable level. We did not bother double digging the beds. We then mulched with hay purchased from the local garden store to avoid erosion until everything was planted up.
We don't have clearly defined overflows, although the edges of the beds are lower than the centers so the water will go around the beds should it ever rain that much. We have had quite a bit of rain so far this year, and overflow has not been an issue - relatively loamy and uncompacted soil combined with the small size of the swales has hopefully mitigated this problem. The soil in the mounds has staid pretty moist, though the frequency of summer watering will be the true test.
(NOTE: In hindsight, it is important to get hay without grass seeds in it!)