In the past, Tzalmon stream flowed to the west, to the Mediterranean Sea, but when Jordan Rift was created, the basic water drain diraction changed. "Young" stream channels began to flow east to the base of the new and deeper drain (The Kineret -Sea of Galilee), began undermining fast backward. These streams hit the watershed captured the streams (they changed the direction of their flow)of  the rivers that flowed west.