A river’s sinuosity is its tendency to move
back and forth across the floodplain,
in an S-shaped pattern, over time, leaving behind
scars of where the river channel once was.
Hydrodynamic forces on a rotating planet mean
a stream will flow in a straight line only
if some strong physical structures constrain it.
A stream constrained by linear hard banks
develops large vertical sinuosities undercuts
the banks. A flat, hardened bottom will
enlarge horizontal sinuosities reach laterally
erode riparian materials. Constraining both sides
and bottom builds up momentum and kinetic
energy manifests intensified turbulence
downstream Sooner or later the self-organizing
turbulence of a flowing stream breaks down