A composition and method of protecting the protection of an exposed body of water comprising 5-95 wt % silicone polymer; greater than zero percent to 90 wt % carrier material; and greater than zero -20 wt % surfactant. The method includes the steps of adding the composition to the surface of the water and allowing the composition to form a liquid film across the surface of the water. The film is effective for reducing evaporation of water from the surface.