Comments by "Reecom98" (@reecom9884) on "Massive eruption in Johannesburg sends cars flying" video.

Down the center of the street where the rainwater and sewer lines are indicates that explosives gases had accumulated and detonated over pressurizing the sewer line. In modern sewer systems, manholes covers would shoot upward to release the pressure like a pressure relief valve on a hot water heater.
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@otozoli2315 In Mexico, raw gasoline was leaking into the sewer lines causing the massive explosion as the gasoline fumes, which is heavy, accumulated in the sewer. In this case it appears that methane gas from the sewage decaying ignited; methane is a light gas and would normally rise out of the sewer through manholes and rain gutters.
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In America when you see a manhole cover flying in the air, it’s an electrical vault fire explosion. Electrical utilities are underground. The main storm water/sewer line is underground below the subway rail lines. In a hurricane street flooding and subway flooding is gravity drained to the storm water/sewer main line below. The main problem here is storm water/sewer branch lines causing a sink hole in the street from leaking. As soon as people complaint about odors they check it out for gas.
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@theeraphatsunthornwit6266 In this case it appears that methane gas from the sewage decaying ignited; methane is a light gas and would normally rise out of the sewer through manholes and rain gutters.
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