Culverts, aqueducts, etc, yes. It all has to be maintained. Even when it's designed well (and the current design is minimal); all those measures have to be kept

Culverts, aqueducts, etc, yes. It all has to be maintained. Even when it's designed well (and the current design is minimal); all those measures have to be kept clear of obstructions. In this case they were not, and very likely still are not.