the bank of a river
The material deposited by a river is called sediment. The bits of organic debris such as leaves and stems is detritus. Sediment includes detritus, inorganic material such as pebbles, sand, clay and other rock bits.
I would call it a sediment.
sand bars
because of the black sediment left after fllods
Call your state government to have them research who gave them your account if it was not you.
Wind erosion and sediment transport by wind.
The abrasion and attrition combined with hydraulic action on the river bed and the river banks erode away the underlying rock which results in small grains of rock we call sand. Depending on the speed of the river and the size of the particles, the sand will be deposited by the river at different stages (usually though it is found near the mouth of the river).
sediment
Much of the coarser sediment material supplied by rivers settles out near shorelines or on beaches.
You call the bits of soil sediment.
sediment
Brazilians call amazon river :river sea