Oren wrote, on Thu, 11 Dec 2014 13:06:55 -0800:
I think all the other drainage pipes must be buried because I've never seen them pop out of the ground like this one does.
I suspect there are at least three or four outlets, as the house is on a hill so all four sides slope downward, so, it wouldn't make sense to curl around the house from the other side to here.
So, I think, the system was designed to be totally underground. That means, I think, that there "may" be a holding tank somewhere.
Maybe it goes into the leach field system? That one set of outflow pipes (black and white) is in the general vicinity of the leach field.
Is it normal for roof drainage to go underground into a leach field?