Border or flood irrigation is an extension of basin irrigation to sloping, long rectangular or contoured field shapes, with free draining conditions at the lower end. These systems divide the paddock into bays separated by parallel ridges/border checks. The sloping area to be wetted is contained by berms spaced 60-120 cm apart. On steeply sloping lands, ridges are more closely spaced and may be curved to follow the contour of the land. Water is applied to individual borders/strips from small hand-dug checks from the field head ditch.

Sloping borders are suitable for nearly any crop (orchards, vineyards, pastures and grain crops), except for those that require prolonged ponding. Soils which have moderately low to moderately high intake rates can be efficiently irrigated with this technique.