I had a customer call me last week with a water leak. I don't normally get involved with plumbing, but I did it as a favore to my customer. Anyway, when I got to the customers house I saw that the area around the main water supply shut-off valve was flooded. After some digging I found a leak at the 90deg elbow just below the shut-off valve. To my surprise the 1 inch supply line from the meter to this valve was some sort of black plastic - perhaps HDPE or irrigation line of some sort. It was connected to the 1 inch copper at the valve via a barbbed copper fitting. The house was built in the 70's. I have never seen anything but copper supply lines used around here for potable water. Has anyone seen such a thing?