Norman Rockwell Museum's Four Freedoms forum series returns at 5:30 p.m. Thursday, Sept. 22, asking the question, "what's in our water?"

The forum will explore current challenges to the environment, their effects and potential risks to our health, and ways in which information is disseminated.

Featured speakers include Jane Winn, executive director, Berkshire Environmental Action Team; Lee Hauge, president, Friends of Pontoosuc Lake; and Tim Gray, founder, Housatonic River Initiative.

The program is free and open to the public.