Here's a link to cold's pond. It has some pics of the dam. Perhaps this will help in seeing the scenario of grade. I think he has enough drop to get a siphon to work. Perhaps not all the way to the bottom of the pond, but he should be able to pull a lot of the water out.

http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Main=28844&Number=370017#Post370017