It alludes not only to the water shortage affecting humans, but also to that of the forests. The surface of the glass is created by the structure of burnt wood, it is rough and natural.
The triangular shape is intended to attract the user‘s attention and at the same time allow the carafe and glass to interact by placing them back to back. This interaction is a symbol for the trees and the water, without one of the two, survival is not possible for us humans.