A violent storm has caused the worst flooding in 100 years on my favorite island of Madeira. (Reference -- December 15th postings) There is one photo with a sailing ship in the harbor. If you look to the right in that photo, you will see a tall bridge. A huge, deep ravine follows the mountain down to the harbor. It would appear that the flash floods followed this ravine (which is designed to handle normal flooding) and well as other venues:
You may have to copy the link and paste it to Google to see it.