<P> In south east Bangladesh, in the Noakhali district, cross dams were built in the 1960s whereby silt gradually started forming new land called "chars". The district of Noakhali has gained more than 28 square miles (73 km) of land in the past 50 years . </P> <P> With Dutch funding, the Bangladeshi government began to help develop older chars in the late 1970s, and the effort has since become a multi-agency operation building roads, culverts, embankments, cyclone shelters, toilets and ponds, as well as distributing land to settlers . By fall 2010, the program will have allotted some 27,000 acres (100 km) to 21,000 families . </P> <P> A main source of silt in urban rivers is disturbance of soil by construction activity . A main source in rural rivers is erosion from plowing of farm fields, clearcutting or slash and burn treatment of forests . </P> <P> The fertile black silt of the Nile river's banks is a symbol of rebirth, associated with the Egyptian god Anubis . </P>

Fine silt deposited by rivers along its banks