Falling into water suggests being emotionally overwhelmed or in a difficult situation. Falling into clear, clean water means the crisis will soon be resolved. Falling into muddy water or rough waves warns of serious trouble ahead. Swimming powerfully in the water symbolizes having the strength to overcome any difficulty.
Falling into water carries similar symbolism to a flood dream, but with a different focus — where a flood is emotion pressing in from outside, falling into water reflects being already immersed in that feeling right now.
The sea, vast and unfathomable, often represents the unconscious as a whole and an overwhelming, undefined anxiety; a river, which flows and moves, more often represents the passage of time or a sense of having lost direction at a particular life stage.
Whether you swim out on your own or are rescued by someone else is a key detail — being rescued often suggests you're ready to accept help, or that your unconscious already recognizes you have someone to rely on.
Natural phenomena in a dream like "Falling into the Sea or River" are traditionally read as symbols of emotional flow or a major life turning point. Modern psychology often connects such large-scale imagery to feelings about a recent change that felt beyond your control.
Was there a major recent change or decision in your life?