In this location, Redwood Creek is concentrated into a narrow channel. This made the water a bit deeper than elsewhere, allowing it to appear like an actual creek rather than, well, just a bunch of wet rocks. :) The gentle flow of the low stream suits well the soft moss the covers the rocks above it.
Everything is flowing -- going somewhere, animals and so- called lifeless rocks as well as water. Thus the snow flows fast or slow in grand beauty-making glaciers and avalanches; the air in majestic floods carrying minerals, plant leaves, seeds, spores, with streams of music and fragrance; water streams carrying rocks... While the stars go streaming through space pulsed on and on forever like blood...in Nature's warm heart.
-- John Muir