Yes, I think I see what you are getting at: The only thing that affects the flow of a river is gravity. Put simply water flows downhill. But because water is a fluid the graviational effect of the moon causes tidal flow which has an effect which we see in estuaries, that is rivers where they enter the sea. In aeas of the earth which have a small tidal range rivers do not have estuaries they form deltas....
By definition, all rivers flow downstream, or down river. The Mississippi River flows south out of Minnesota and empties into the Gulf of Mexico from Louisiana.
Jacques Cartier sailed up the St Lawrence River, as far as the Lachine Rapids, in search of a route to Asia. When he found that the route was impassable, he then turned around sailed back down the St Lawrence. The concepts of "up" and "down" a river relate to the flow of the water, not a direction on a map. Travelling up a river means travelling against the flow. Travelling down a river means travelling with the flow.
The Nile River flows north. Therefore, if you are looking at a map of Egypt it would flow up the map. When you look at a map North is always up and South is always down.
Down
on the slope down from the top of the river, to the bottom of the river
The Colorado River flows fast because it flows down hill in the grand canyon and picks up speed.
it slows down because first it rushes down from mountain and then slows down right at the end when it goes into the sea/ocean/lake.
down-hill
Springs and glacial melt.
up stream
i can't flow up
Upstream or up river