Gas quality lowered when a station is at the bottom of a hill?

Question

Is it true that if a gas station is at the bottom of a hill it will have lower quality of gas due to water flow as it goes down the hill? I have been going to a gas station that is at the bottom of a hill and someone told me that when the station is at the bottom of a hill the water from rain washes down the hill and leaks into the tanks which lowers the quality of the gas. Is that true?

Answer 1

There is no direct connection between the quality of the gasolene and the relative amount of rain that falls and collects around the filling station. The tanks of gasolene that they have are below ground level are normally sealed against ingress of water or other materials.

Should any water get in to the storage tank it would go to the bottom of the tank and not get pumped out with normal use. This is arranged by making the pipe inside the tank not go to its lowest point, thereby allowing for a certain degree of accumulation of unusable material that is more dense  than the gasolene, including water. These tanks are usually cleaned out at regular but infrequent intervals.

Injecting water in with your regular gasolene may even be good for your engine, provided it is well-mixed. This is because it will produce steam and lower the temperature when hard running. It was used in aircraft propulsion when they had piston engines. In that application, water injection improves the take-off performance and helps the engine to develop more power for the same temperature.

Answer 2

The underground gas tanks should be sealed, so no water should enter the tank. But I would be concerned if I saw water pooled around the tank filler ports (where the tanlker delivers gas to the gas station).

Answer 3

No it does not. Gas quality is the same in any location, it doesn't have anything to do with if its at the top or bottom of the hill. Underground gas tanks are securely sealed, nothing gets in and nothing gets out. That's to make sure that gasoline never leaks out into the ground, that would cause serious environmental issues in the future. So no, water is not going to get into the gas tanks that are underneath the ground at gas stations.