Compare "Somewhere in the desert there's a hole" with the line "drove Rommel to his desert hole" from the song "Third Secret" on the Legendary Pink Dots album "The Maria Dimension".
Somewhere in this "desert", there's water. Real water, not a mirage. If water is a symbol of the emotional world, then these emotions are running hot and cold. Passionate and impassive. When we find this oasis we can hide there from the world, undercover, making the most of our time until the situation is right for us to go out into the world and make a change. What kind of change?
The line "we will pour our jars in reservoirs" could refer to the sixties scare that someone would contaminate the water supply with LSD, but it could also mean banding together to combine our resources and knowledge (as in forming musical units) to create something beautiful. To turn the world off evokes pulling the plug on the global power grid, so that in the ensuing darkness everyone would be able to see quite vividly the orange shaded sunset that the artist has made (on a whim, just because he liked it that way!)
A song for revolutions!
OO EE OO