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Risingwater pressurensideof nsideof I lGI l round sidemanhoemanhoeInstall valves on the inside of the manhole wall without digging into the roadStrong earthquake vibrationWhen the groundwater pressure increases, the valve automatically opens and groundwater flows into the manhole. 　⇒ Lowers the groundwater pressure and prevents lifting.Tilting connections are used for the connections between sewer pipes and manholes which are susceptible to earthquake damage.Rubber blocks which absorb earthquake vibrationThe earthquake-resistant water pipes will use earthquake-proof couplings that prevent the pipe from being disconnected.Pressure adjustment tabValveMetal screenManhole wallPressure adjustment tabValveMetal screenManhole wallJoints can move with the earth without becoming disconnected.WaterWaterpressurepressureSoil liquefactionSoil liquefactionCatches andwon’t come loose!Earthquake-resistant water pipesMeasures to prevent manholes from becoming liftedEarthquake-resistant connections between sewer pipes and manholes　When an earthquake disaster occurs, the lifelines, such as water and sewerage, electricity, gas, and telecommunications, will be affected.　In order to minimize damage during a disaster, the following preventive measures have been taken for water and sewerage.　If water and sewage pipes are damaged by a large-scale earthquake, not only will it be difficult to obtain drinking water, but toilets and baths will be unavailable, and leakage of water pipes and sewage can damage people's houses, force a stop to business activities, and in other ways have a severe effect on residents' lives and property. Road collapses caused by leaking water or lifting of manholes by liquids can obstruct vehicle traffic and otherwise interfere with emergency response activities.　In order to avoid such a situation, we are taking measures to make earthquake-resistant water pipes, earthquake-resistant connections between sewer pipes and manholes, and to prevent manholes from becoming lifted in areas where liquefaction is likely to happen.(3) Earthquake Disaster Prevention Measures for LifelinesEarthquake disaster prevention measures for lifelines such as water, sewerage, etc.36