These pictures were taken during one of our Sunday walks towards the end of May. The aqueduct carries the C&O canal across the Monocacy river.
This kind of flooding happens every once in a while, and most often during the spring season when we get a lot of rain. The accumulation of the debris is somewhat unusual. The last time it happened they had to bring in heavy equipment to remove the tree branches that were caught on the structure of the aqueduct and putting pressure on it.
The following picture was taken during the same walk at a different location on the trail. This is upstream on the Potomac river.