The mountains they are piped over are not the High Sierra, but the narrow coastal ranges near Santa Clarita. That itself requires a massive amount of energy. H

The mountains they are piped over are not the High Sierra, but the narrow coastal ranges near Santa Clarita. That itself requires a massive amount of energy. Here is the full map of the system: https://en.m.wikipedia.org/wiki/Los_Angeles_Aqueduct#/media/File%3ALos_Angeles_Aqueduct_Map.png https://en.m.wikipedia.org/wiki/Los_Angeles_Aqueduct#/media/... Pumping over the Cascades would require much more energy since there are no natural valleys connecting the water rich parts of the PNW with CA. It's a very thick wall of mountains that you would have to pump water up and down repeatedly.