There were many odd shapes on the face of the Grand Coulee Dam.  With the water running down in parts and some of the structure of the dam breaking up the smooth face, it was possible to see some unusual patterns in the surface.  There were many power lines strung across the water in front of the dam so these could distract from the shapes so I tried moving around to be between each of the lines.  With the texture of the face of the dam it was possible to look closely at elements and have no obvious clue what they were.