Area around Mt Teide

Here is a photo of the bizarre landscape around Mt Teide in Tenerife
... I imagine the surface of the moon would look something like this
(without the plants and people)... it could be background scenery to a
Salvador Dali painting - it looks so surreal. I find it hard to believe
that Tenerife's basic water supply depends on the melting snow on
Teide itself, when the region looks so dry and barren.... I didn't see
any cascading water on the side of Teide that we were looking at.