How to determine cause of water in natural gas line? Gas service was shut off for a number of months (at least 3, at most 6) and when restarting service could get no gas flow due to COPIOUS amounts of water in the line (Gas meter was actually FULL of it, and water GUSHING out of pipe near basement water heater)! Seems that this is far too much to be condensation in the line even after 6 months (in Los Angeles), so how does this much water enter a gas line and how to find the source? And please, since $ is practically speaking nonexistant, no "call a plumber..." responses; the goal here is to avoid that if at all humanly possible, or at the very least minimize the bill when it is inevitable by troubleshooting as much as possible beforehand to minimize billable hours. In all likelihood this will involve trudging under the house with a flashlight whilst tracing the line back ffrom the neter, but what to look for specifically and are there any usual or likely suspects to inspect for starters? Lastly, any idea what kind of financial damage this kind of thing will do if we can't find the problem ourselves, or if we can and just need a pro for the repair?

When gas lines were run a "drip loop" was usually installed. This was simply a tee with a drop pipe positioned down just after the gas meter. Its fuction was to catch any water or condensate that might be in the line before it got to the burner. In time condensate had bulit up to the point that it came into the house with the gas and killed the pilot light. Locate the drip loop, shut off the gas at the meter and drain it. It's worth a try. Drain the line through the drip loop and turn on the meter again. Is there water in the service line before then meter? How much? Let me know, Tom

Sometimes called a "dirt leg". You'll also find one at the heater.

If there is suspician of a leak, you can always pressure test the line.

Some plumbers connect gas line through Pressure Relieve valve located on your hot water heater. Idea behind this approach is that if pressure, or heat, is too high, pressure relieve valve will activate, fill gas pipe with water, killing the pilot light in the process. Chances are your Pressure Relieve valve activated due to high pressure and keep releasing water into your gas line.

If your gas line is indeed connected to the pressure relieve valve than you would have to replace your pressure regulator and than replace the pressure relieve valve as well.