Basic objective of this lecture is to present on Work of Rivers. The erosional work of streams/rivers carves and shapes the landscape through which they flow. Three functions of rivers; Erosion; Transportation and Deposition.. The energy in a river causes erosion. The bed and banks can be eroded making it wider, deeper and longer. There are four main processes of erosion that occur in rivers. These are: hydraulic action; abrasion/ corrasion; attrition; and corrosion.