A Study on Urban Groundwater Environment in Southeast Asian Countries

In this study，following research works were conducted: Data collection and/or analysis associated with theimpact of groundwater extraction on urban groundwater环境in Hanoi，Vietnam Establishment of simulation modeling on groundwater behavior due to groundwater extractionin Great Bangkok areas, ThailandFirst，in order to collect data on results of groundwater monitoring and investigate current situation ofgroundwater Environment in Hanoi，our research group has held workshop in Hanoi together with Vietnamese researchers和工程师。a result of investigation，following findings were obtained: Little decrease of pore water pressure in aquifers due togroundwater extraction是观察，because the amount of Groundwater usage currently balances with water supply from surroundingrivers.secondly,prediction of groundwater behavior and相关土地subsidence due to groundwater extraction inGreat Bangkok area conducted. Results showed that the control measures…More on groundwater pumping issued by Bangkok Metropolitan Office effectively helped todecrease the rate of subsidence in central area of Bangkok. However，它predicted that additional land subsidence in surroundings areas amounts to 0.5m-1.0m，虽然选择的比例subsidence decreases，the sensitivity analysis of uncertain factors involved in evaluation of land subsidence made itclear that clay contents involved in angkok aquifers are dominant one.Furthermoreflood risk analysis against settlement of dyke along Chao Phraya riverwhich flows through Great Bangkok area, was conducted. In detailexceedanee可能性of land subsidence to allowable settlement was selected as index toinvestigate flood risk. Finallyfollowing findings were obtained: Flood risk along Chao Phraya river varies from place to placebecause of subsoil profile and location of pumping wells. Uncertainly associated with clay contentsinvolved in Bangkok aquifers是dominant risk factors against flood. Less

In this study, the following research works were conducted:・Data collection and/or analysis associated with the impact of groundwater extraction on urban groundwater Environment in Hanoi, Vietnam・Establishment of simulation modeling on groundwater behavior due to groundwater extraction in Great Bangkok areas, ThailandFirst, in order to collect data on results of groundwater monitoring and investigate current situation of groundwater Environment in Hanoi, our research group has held workshop in Hanoi together with Vietnamese researchers and engineers. As a result of investigation, the following findings were obtained:・Little decrease of pore water pressure in aquifers due to groundwater extraction is observed, because the amount of Groundwater usage currently balances with water supply from surrounding rivers.Secondly, prediction of groundwater behavior and related land subsidence due to groundwater extraction in Great Bangkok area was conducted. Results showed that the control measures … More on groundwater pumping issued by Bangkok Metropolitan Office effectively helped to decrease the rate of subsidence in central area of Bangkok. However, it was predicted that additional land subsidence in surroundings areas amounts to 0.5m-1.0m, though the rate of subsidence decreases. In addition, the sensitivity analysis of uncertain factors involved in evaluation of land subsidence made it clear that clay contents involved in Bangkok aquifers are dominant one.Furthermore, flood risk analysis against settlement of dyke along Chao Phraya river, which flows through Great Bangkok area, was conducted. In detail, exceedanee probability of land subsidence to allowable settlement was selected as index to investigate flood risk. Finally, following findings were obtained:・Flood risk along Chao Phraya river varies from place to place because of subsoil profile and location of pumping wells.・Uncertainly associated with clay contents involved in Bangkok aquifers is dominant risk factors against flood. Less