"Moving water mains posed," said the headline, but my tired brain couldn't make any sense of it. I mean, I understand the need for mobile phones, but mobile water mains? Why would anyone want underground water lines to shimmy and dance and move around? And what were they posing for? Plumbing-porn mags? Or were those mobile water mains simply impersonating something else, perhaps posing as presidential candidates or police officers? In that case, those moving water mains ought to be arrested. Cuff 'em, Dano.
But wait! Maybe the water mains themselves are not doing the posing! Suppose some person or persons unnamed poses--what? A question about whether water mains should be moved? Perhaps someone in a position to pose such a question proposed that it would be advantageous to move certain water mains, but it sounds odd to speak of a proposal's being "posed," unless it's a particularly photogenic proposal, in which case I stand corrected.
Here's my theory: someone posing as a headline writer moved some some words around to fit the available space and produced a headline that posed more questions than it answered.