As the river flowed through the area, it deposited sediment in deltas and during flood stages, deposited sediments on the surface of the wetlands themselves.
(the river; flowed; through the area) (it; deposited; sediment; T:in deltas and during flood stages; T:As the river flowed through the area)
the river it
flowed deposited
through the area
sediment T:in deltas and during flood stages T:As the river flowed through the area