No question.
But where does the Israeli-Palestinian wall parallel and block access to a river flowing through a desert environment?
Would the Israelis have built a wall along the Jordan? I doubt it.
For your amusement the Israelis wall. It must be a nightmare to man, but they manage.
Beyond that, I have been to the Israel / Jordan border and guess what, there were many spaces where there was nothing but wide open land between the two countries — no fence.
http://markraff.files.wordpress.com/2011/06/dead-sea-fence.jpg ~ neat shot of a piece of fence along the Jordan where the river runs into the Dead Sea. Little appreciated by outsiders every single drop of water flowing in the Jordan is already spoken for by the downstream users and is fully encumbered by laws of ownership, municipal authority, national laws, and international treaties and agreements. Where they don’t have a fence there are guys who are watching what you do and may shoot you!