Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Evening Poster

A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW24] Hydrological change after the 2016 Kumamoto earthquake

Tue. May 22, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Jun Shimada(Graduate school of Science and Technology, Kumamoto University), Kei Nakagawa(Graduate School of Fisheries Science and Environmental Studies, Nagasaki University), Takahiro Hosono(熊本大学大学院先導機構, 共同)

[AHW24-P02] Effect of the reduction of artificial groundwater recharge through abondoned rice paddies at Mid stream area of Shira river and its sorrounding area caused by 2016 Kumamoto earthquake to the local groundwater resources

*Jun Shimada1, Kiyoshi Ide2, Azusa Okumura2 (1.Emeritus Professor, Kumamoto University, 2.PD researcher, Priority Org., Kumamoto University)

Keywords:2016 Kumamoto Earthquake, artificial water ponding through abandoned rice paddies, artificial groundwater recharges

Because of the intensive groundwater use, Kumamoto area have settled more than 100 monitoring wells to cover over 30 years for its sustainable management. Those monitoring resuts show the long term decreasing tendencies of the groundwater level and as the drastic countermeasure for this, the artificial groundwater recharge thorough abondoned paddies of the Mid stream area of Shira river, where is known as relatively high recharge possibility by thier hydrogeological condition, has been started from 2004 by the cooperational activities of the local goverments and agricultural societies. Kumamoto Earthquake 2016 has severely damaged the paddies, farm lands, and irrigation channels of this area and the artificial groundwater recharge has decreased down to 30 %. In the year 2017, the damage has well recovered mostly and the artificilal recharge comes back almost 90 % level. This temporal decrease of artificial recharge should reflect to the local groundwater resources if we carefully check the groundwater monitoring data in the recent 2-3 years which cover before and after the earthquake.