View of a typical plowed field in Upper Egypt. Note the small channel that brings water to the various small plots. In order to water these plots a small opening is made in the small channel to allow water to flow into the plot. Once the plot is watered, the opening is closed!
Compare Deut 11:10 " The land you are entering to take over is not like the land of Egypt, from which you have come, where you planted your seed and irrigated it by foot as in a vegetable garden." The use of one's foot to open a small opening is one possible interpretation of 'irrigating by foot.'
This picture was taken in December.