I agree with Reene completely and I want to believe that it was intended as metaphor in addition because when I first heard the title - as I have mentioned in other responses here - I thought it sounded like a cliché. Surely, I hope, an author or editor would not select a title that simplistically. Initially the title made me less interested in reading the novel, but the more I read, the more I saw a deeper connection between the characters, their actions and involvements, and the title. Early on in the novel, the Dillards are facing extreme difficulty until Marris, along with Sadie and others, (metaphorically, the creek), comes to their aid. In the chapter titled Tattler Swann, we see how Jerome Biddle is facing capture and nearly drowned until Tattler and Sadie reclaim him. Sadie, too, seems nearly ready to "go under", but in several instances others such as Marris, Kate, and Birdie come to her aid. Each of these individuals and situations may be read metaphorically.