It is important that the water does not carry much sediment.
It carried soil and sediment, but with much less energy than its predecessor.
The Yellow River carries more sediment than any other in the world.
The river carries sediment which makes the downriver land fertile.
Rivers on that side therefore carry sediment away from the rift valley.
The rivers flowing at high speed in the mountains carry sediments.
That created rain runoff carrying sediment to the canal network.
Also, water carried over land by the storm surge carries sediment away as it flows back out to sea.
This secondary flow carries sediment from the outside of the bend to the inside making the river more meandering.
The river works as a density current, because it carries sediments along the sea floor and has a higher salinity than the surrounding water.