Prediction of the Groundwater Variation in the Reclaimed Land

In Nagasaki Prefecture, at present, Isahaya reclamation work is in progress. In order to predict the impact upon the level of groundwater due to a construction of sea-dyke and reclaimed projects, mathematical simulation has been performed and an appropriate pumping rate discussed considering a location of wells in and around the reclaimed land. It is well known that lowering of sea level causes similar change of groundwater level, while its opposite change, that is rising of groundwater, results from moving of shore-line apart from its position. Considering a fact such that groundwater level is one of the important factors for an irrigation, it becomes necessary to exactly predict an extent of rise and fall in groundwater level. At the same time, investigation of horizontal distribution of velocity of groundwater cannot be avoided for detailed discussion of water environment. The above-mentioned mathematical simulation can make clear these figures. From now, precise estimation of these figures using a highly-sophisticated model becomes more important for the environmental assessment. Proposed model in this paper is expected to be developed further