Reflections offer a useful subject when a waterside walk feels visually quiet. Trees, sky and nearby structures can appear as broken shapes rather than recognisable objects. Looking at these shapes encourages a slower kind of observation.
Start from a comfortable established viewpoint. Describe the largest areas of light and dark, then notice their edges. A reflection might look sharply outlined in one moment and become a loose pattern in the next.
If taking photographs, make a small sequence from the same position rather than searching continually for a better angle. Review the pictures together and choose the one that best matches the feeling of the pause.
A journal entry can also record why you put the camera away. Sometimes watching the changing surface is more rewarding than keeping an image. The record still has value when its most important part is a few careful sentences.