Water flows down the ridges in ditches and is diverted to flood across the land.It is often necessary to have small spreader ditches to redistribute water that naturally accumulates in swales.

• 水在沟渠内沿渠埂向下流动并被引出来灌溉农田，时常需要临时开挖小分水沟把聚集在洼地里的水再次分配。