I'm curious as to why 20' lengths of pvc are used for water supply line in some areas. My brother in Kansas has that and he is on his second leak in five years, it's a county water district. What's up with that?
I don't think I've seen that used around here. Not sure what they use in town, but the well to house supply lines are done with the rolls of black plastic pipe here.
The advantage of using pipe with a gasket is that it can contract and expand with the soil. A common reason for pipe failure is fatigue from movement in the ground. Black Poly pipe is one of the worse for this and in my part of the country, it's a full time24/7 job for several crews in the city to repair them.
If the leak is happening right after it's been buried, the cause is probably from being able to move too much in a bend or curve. The fill is never as compact as the undisturbed soil and that allows the pipe to move more then it should. Sacks of concrete should be placed in the hole to keep the pipes in place until the soil compacts.
Did you use grease to slide the pipes together? Not using it can cause the gaskets to turn and result in a leak.
Before doing anything drastic like cutting the pipe, dig down at intervals and look for moisture in the trench. 14 gallons isn't very much and it will take awhile for it to surface, or it might never come to the surface. The bottom of the trench should hold enough water that you should be able to see it when you get to it. Of course, with rain, that wont work until everything is dried out.
How do you know you have a leak? I had an issue with a water district on a house that I was flipping that said I used 40,000 gallons of water in one month in an empty house with the water turned off at the house. I spoke to a guy at another water district and he said that if the water supply was surging, and it was an old meter, then water would go through the meter under pressure, then back when the pressure dropped. Every time the pressure increases, the meter reads it as water going through, but when the water pressure drops, the meter doesn't read it, resulting in thousands of gallons on the meter that I never used. In this case, they replaced the meter and added a backflow device. Problem solved.
How much water pressure is at your house? If it's too high, over 80 pounds, the water might be going through your toilet. Ideally, water pressure in a house should be around 60 pounds. If you go much higher then that, the valve in the toilet bowl will leak water through it. That water goes through the toilet and down the drain without you ever knowing it. You wont hear it or see it, but it's ongoing all the time. Usually this adds up to thousands of gallons a month. You need to measure the water pressure at the house. You can get a gauge in the sprinkler department of any home improvement store to that attaches to an outdoor spicket that will tell you how much pressure you have at the house. A house downhill from the supply will increase water pressure from gravity.
Good luck,
Eddie
