what is a swale
A swale is a low tract of land, especially one that is moist or marshy. The term can refer to a natural landscape feature or a human-created one. Artificial swales are often designed to manage water runoff, filter pollutants, and increase rainwater infiltration.his type of swale is created by digging a ditch on contour and piling the dirt on the downhill side of the ditch to create a berm. In arid climates, vegetation (existing or planted) along the swale can benefit from the concentration of runoff.