Water Storage Capacity Oo Contour Furrows in Montana

Abstract

A field study in eastern Montana related water storage capacity of contour furrows constructed by Model B furrowing machines to furrow age. New contour furrows have a water storage capacity of nearly 1 inch, but this decreases with time owing to natural weathering, intrafurrow dam failure, and furrow breaching. Contour furrows have an average effective life of 25 years, but this ranges from less than 20 years to more than 35 years, depending on initial construction. A new furrowing machine design is suggested that would leave intrafurrow dams of undisturbed soil material, resulting in furrows with either the same storage capacity but at a greatly reduced cost per acre, or over twice the storage capacity at about the same cost per acre as furrows built by a Model B machine.