The study looked at how irrigation affects water availability in the Lake Tana sub-basin in Ethiopia. They found that small-scale irrigation is expanding rapidly in the area, leading to concerns about water scarcity. Most of the water for irrigation comes from surface sources, and during the dry season, about half of the available water is used for irrigation. This can lead to water shortages in some parts of the sub-basin. The researchers suggest that better management of irrigation is needed to prevent water scarcity in the future.