i like yer summer vs winter "tree water use" speculation as well Eric. i take it you have mature trees all the way up to pond's edge? they probably have all kinds of feeder roots along sides of pond.
as long as you are doing nothing wrong, ya need some no tresspassing signs, and to rebuild yer second dam. get to know yer local sherriff. if the guy persists in tresspassing and property damage, wake his ass up with the law. i'm sorry to hear that too, but private property is PRIVATE PROPERTY. however eric, i imagine you to be a kinder and gentler man than i, just my two cents.
