Missing: 46,000 gallons of water

Yesterday my wife and I came home from working at our store in a neighboring town at about 5:30 pm. On our front door was a note from the county water department stating they had shut off our water due to a leak on my side of the water meter. It was too late to call the water department so we went waterless; using water out of our cistern for toilet service. I called the water department early this am and made arrangements for someone at the water department to meet me o we could determine the exact location of the leak. I have insurance that covers the water line from the street to the house. The water department personnel arrived right on time and I was instructed top turn off the water going into the house in the basement and they would turn the water back on out at the street and we could determine whether or not the main feed line was leaking. It wasn't. So the leak had to be in the house. But I had followed the water line from where it enters the house all the way through the house and no leaking water was found. As the water department said the meter showed 46,000 gallons had been used; that is one heck of a lot of water for it to not show up anywhere. So the water inspector came into the house and followed the line through the house. He was shaking his head and saying "If the leak is in the house you should have a basement full of water". I agreed. No sign of extra water was evident. Finally we got to the very back of the house where the water line goes into the laundry room. The laundry room has a water shut-off valve. We closed off that valve and the noise of running water ended. The leak is in the laundry room. But the laundry room is attached to the basement but sits above the basement. Yet there is absolutely no evidence of water outflow. I have a crew coming in tomorrow to fix the pipe; but where in this crusty old brick is the house hiding 46,000 gallons of water? I've been all around the house and especially the laundry room searching for floods of water. Its been raining today, but even at that, wouldn't you think 46,000 gallons of water would have left some trace? I realize this is not anything paranormal, at least I don't think it is. Unless I have a very thirsty haunt. Or maybe I simply flooded a tunnel. There are tunnels in this town but I never found one under this house; but who knows?