The Kenya Climate Smart Agriculture Project (KCSAP) Cotton Multiplication

This is also known as surface irrigation. Here the farmers flow water down small trenches or well-made furrows running through their crops. The water comes from the main canals and its directed through furrows in the entire farm. Its widely practiced within the irrigation scheme with crops planted on top of the furrows. Water flows in the whole farm by gravity.  Though its not the most efficient, the farming households see it as affordable cheap and easily implementable. low-tech. It was noted that a lot of water can be lost from runoff at the edges of the fields.
https://www.kalro.org/kcsap/