River delta slope offshore, waves will make river deltas smoother. Waves can also be responsible for carrying sediments away from the river delta, causing the delta to retreat. For deltas that form further upriver in an estuary, there are complex yet quantifiable linkages between winds, tides, river discharge, and delta water levels. Erosion is also an important control in tide-dominated deltas, such as the Ganges Delta, which may be mainly submarine, with prominent sandbars and ridges. This tends to produce a "dendritic" structure. Tidal deltas behave differently from a river- and wave-dominated deltas, which tend to have a few main distributaries. Once
Red River Delta the East Asia coast. Its catchment covers parts of China and Vietnam and its water and sediment discharges greatly influence the hydrology in the Gulf of Tonkin. By the rich natural resources and favorable natural conditions, the delta has become an area of active economic development and high population density. In 2003, of the 78 million people in Vietnam, almost a third (24 million) live in the Red River basin, including over 17 million people in the delta itself. There are many large industrial zones in the Red River delta clustering in Viet Tri, Hanoi, Haiphong and Nam Dinh. Agriculturally