THE RIVER THAT NEVER FREEZES

Not far from my hometown there is a small river,  a stream that comes from the mountain and runs down to form a big pound.
This river and pound don´t freeze in wintertime. Many people find this strange, because everything freezes here during the winter. Tempearatures can get down to -50 celsius and it´s cold. So why doesnt it freeze?
The legend says that uldá/gufihtar (undergound people) live under this river, and thats why it never freezes. During the spring, when all the snow melts, sometimes the water is not so good in the tap and we have to go and get water from nearby springs. This river is one of them, so the water is supposed to be extra clean and good. Magic water if you ask me!

Can you find any other good reason then that the underground people are the reason this? 😉
Hihi, not me! 😀