I am looking for a short story that I read a few years ago about an island that belongs to the mer-folk/ sea beings. The island lies off a coastal town who connect it to the mainland via jetty/pier and build a dance hall on it. The mer-folk throw up a huge storm on a dance night and separate the island from the mainland once again. They claim back their island. There was good description of the storm and its effect on the dancers I think. I read it in a compilation of spooky stories but I have never found it since. I would love to read it again.