The tide was very high when we got the parade in Cowes. The water level was just below the street level. Naturally, there was some swell, even though we were inside the harbor wall. This meant the water was pushing back up through the drains that normally take water from the street down to the sea. The water would force itself back up through the drains. Sometimes it was just a small amount of water but the bigger waves resulted in a bit more flow back out of the drain. Video is the best way to show this. The metal of the drain cover had the level of corrosion you would expect for something with this proximity to the sea!