"Irrigation canals" refers to man-made channels or ditches made for carrying water to fields and crops. They are designed to provide water to plants and help them grow. Full definition
During the flooding period, the network of irrigation canals and the organic paddy fields close to lagoons become a crucial link between marine and river environments, and provide an important habitat for many species of fish and amphibians, such as damnbusia (Gambusia holbrooki), carp (Cyprinus carpio), fartet (Lebias ibera - an endemic fish of the western Mediterranean Sea), coruna frog (Rana perezi), and others. (fao.org)
He broke ground out of sagebrush using teams of horses and helped to dig early irrigation canals in the area. (fooddrink-magazine.com)
Waterways like irrigation canals and trash - filled sewers helped cholera overrun Haiti in a matter of weeks. (science.sciencemag.org)