yes, right. that was one of the ways they said they were going to be saving money (using gravity to move the water). and agreed on the pig. seems they'd have to be using a pump to move it. especially through the turns.
i think the bottom line is that they use both to a degree - to what degree would be some interesting info to hear.
they initially planned to harvest twice daily, but with the "constant harvesting mode" they've announced that they're in, maybe the pumps are working all the time. if so, that'd be good news for us, not bad news.