2010.4-2011.3 Yearbook of NILIM
Research Summary
River Department
| Reference Number | Y100308 |
| Title | A Study on behavior analysis of shallow underground water |
| Start-End Date | 2009.4-2011.3 |
| Division | Water Management and Dam Division |
| Author | Head, Shinya MITSUISHI Senior Researcher,Yoko YAMAMOTO Researcher, Tadahiro TOYODA |
| Summary | Many problems have emerged with groundwater due to excessive pumping and a decline of rainwater infiltration caused by the progress of urbanisation. The actual problems include ground subsidence, depletion of spring water and intermittent flow of river water. Even though such measures as capping of the pumping yield and the installation of infiltration inlets are being implemented, their quantitative effects have not necessarily been evaluated. For the appropriate use and conservation of groundwater and river water in the coming years, clarification of the mechanism of water flow is essential to properly establish the overall storage potential and behaviour of groundwater with a view to establishing a healthy groundwater cycle. This study intends the development of a three-dimensional shallow groundwater flow model which is capable of analysing the behaviour of river water as well as groundwater in the Nogawa River basin in the Tama River system in order to establish a healthy groundwater cycle system. Using this model, the discharge and recharge mechanism between river water and groundwater is evaluated along with analysis of the changes of the water cycle system to properly analyse suitable groundwater conservation measures. These changes include the occurrence of interrupted river water flow, increase/decrease of the pumping yield and changes of the river water level, groundwater level and volume of spring water due to the implementation of measures to facilitate infiltration. |