A deranged drainage system is a drainage system in watersheds where there is no coherent pattern to the rivers and lakes. It happens in areas where there has been much geological disruption. The classic example is the Canadian Shield. During the last ice age, the topsoil was scraped off, leaving mostly bare rock. The watersheds are young and are still "sorting themselves out." Eventually the system will stabilize. This is why there are so many lakes in Canada.
