Downstream by Supertramp is a heartfelt ballad that explores themes of love, introspection, and the passage of time. The song vividly describes a journey through life and relationships, likening it to a river that flows downstream. With poetic imagery, it captures the essence of longing and the bittersweet nature of memories. Key moments include reflections on past love and the contemplative realization of how life's experiences shape us. It's a poignant reminder of the beauty and transience of life.