There is an entire sub-genre of poetry devoted to rivers and their persistent, meditative flow. Emily Dickinson’s “My River Runs to Thee” compares them to the cycle of life, while Alfred Tennyson’s “The Brook” deems them eternal and Kathleen Raine’s “The River” muses on the dream-state they evoke. For transcendent folk-pop artist Shannon Lay, the river is all of the above: It’s the metaphor driving her latest album, the exquisitely uplifting August (Sub Pop Records, out August, 23rd)—which doubles as an aural baptism renewing her purpose for making music.