Strictly speaking, when talking about a gas pipeline, we should perhaps use the word “gasoduct”, even though this term is not often found in common usage in English.
A “gasoduct” is a steel pipeline used to transport gas under pressure over long
distances, from the extraction site to the consumer areas. It might be buried underground or underwater, or may be above ground.
A “pipeline”, meanwhile, can be used to transport any kind of fluid, including water and oil, so to avoid any doubt, perhaps we should adopt the term “gasoduct”, just as our French counterparts use the word “gazoduc”.