Hyun-A Lee, Yu-lee Kim and Nam C. Woo, Yonsei University
National Groundwater Monitoring Network has been established in Korea since 1995. The network consists of a total of 320 monitoring stations to delineate changes in water levels and groundwater quality in a regional scale. This paper presents water-level fluctuations and long-term changes during last 5 years in the Han-river basin, in which approximately 20 million people (40% of the total population) live. Water-level data used were obtained from 40 of the national monitoring stations. Parametric and non-parametric trend tests including Mann-Kendall test and Sen’s test were used for daily, monthly median data. From the linear regression, about 70% of monitoring wells show trends of water-level rising and none of them show ‘no trend’. On the other hand, in those of non-parametric trend tests, rising and declining trends appeared in 15~39% 7.5~13% of examined wells, respectively. The results of Sen’s test were same with or slightly lower than Mann-Kendall’s. Difference between results is due to removals of weak-linear trends. For local water resource management, the main factors of those long-term trends will be analyzed including climate and hydrogeology. In addition, since many satellite cities have been developed surrounding Seoul, the megapolitan capitol of Korea, socio-economic factors should be also analyzed.
The 2007 Ground Water Summit