"DamNation" is a riveting, award-winning documentary about the tension between harnessing rivers and letting them flow freely. In our little state, there are 1200 dams. In this context, the movie poses questions about the future of our waterways as healthy habitats for both fish and people. Brian Fitzgerald, a Vermonter who is an expert on river restoration, will lead an informal discussion following the showing. The event is scheduled for the SB Community Library, this Saturday, from 1:00 to 2:30 p.m.