And you need to worry about the proverbial water upstream...
Thankfully, milfoil has not been found in Merrymeeting Lake. But the Merrymeeting River and Marsh are full of it. New Durham is trying to do something about it...
http://www.newdurhamnh.us/Pages/NewD..._BComm/aquatic
Why should the Lake Winnipesaukee forum care? Think of where the Merrymeeting River goes...