This is a tidal bore on a river somewhere in Indonesia. A tidal bore is a tidal phenomenon in which the leading edge of the incoming tide forms a wave (or waves) that travels up a river or narrow bay against the direction of the river or bay’s current.
Apparently you can pretty much surf everywhere on Earth now; between man-made desert waves, river waves, ocean waves, Irish waves, AK waves, blue waves, green waves, brown waves, big boat waves, little boat waves, tsunami waves, calving glacier waves, and dynamite waves, not to mention other types of waves.
This video shows you tidal bores and they were surfed. The End.