bostonjd, there have been many prior discussions such as:
http://www.winnipesaukee.com/forums/...ght=lake+level
and
http://www.winnipesaukee.com/forums/...ght=lake+level
Do a search and you will find a lot more. IMHO they do a good job of maintaining the level given all the constraints and the uncertainty of mother nature.
Welcome to the forum.