Built with Silt
Dam! That didn’t happen overnight. It must have been a culmination of the weather of the past six months. One flood after another brought the sticks and leaves and silt. How else could this be built? The dogs do not allow beavers and this is a branch, not a creek. As waterways go, this is one of the meek.
The docile become dangerous when overfilled. Afterward, back to mild-mannered flow, the debris remains with nowhere to go. Remnants become battlements in the new war. Until the next deluge when the rain will bring more.