Thursday, December 17, 2020

River Basics

 River behavior can be understood through both a scientific and historical lens. Its most important principle is that water only moves downhill- it can never flow from the ocean or up into a source. This also means that it's nearly impossible for a river to split into two and drain into two separate river sheds, and that there are only a few dozen examples of it in the world only under special geologic conditions. One of these places is the "Parting of the Waters" in Wyoming- where a river splits into two creeks that drain into both the Pacific Ocean and the Gulf of Mexico, and would theoretically be a natural canal across the Americas if the rivers were fully navigable.

 This also means-

It is nearly impossible for a lake to have two or more outlets

It is nearly impossible for rivers to collide directly- below is the single exception

 

It is impossible for a river to flow from ocean to ocean

It is almost impossible for a river to switch directions seasonally

It is very rare that a tributary comes very close to the source of the river it flows into

It is very rare that a river comes very close to a different outlet than where it terminates


Rivers both influence and are influenced by the topography around them. They are easily detected in a topographic map: