Programme OS3g Climate change: disasters
and extreme events abstract 256
Groundwater Use in Earthquake Emergency: A Case Study in Japan
Author(s): Tadashi Tanaka
Graduate School of Life and Environmental Sciences,
University of Tsukuba, Ibaraki
305-8572, Japan
Tel & Fax: +81-29-853-4208
E-mail: tadashi@geoenv.tsukuba.ac.jp
Keyword(s): earthquake emergency, secure of water, groundwater, countermeasures, registration, well,
monitoring, mega city, Japan
Article:
Poster:
Session: OS3g Climate change: disasters
and extreme events
Abstract Introduction:
Many big earthquakes have occurred in tectonic regions of the world, especially in Japan. Usually,
earthquakes cause damages of lifelines such as water, gas and electricity supplies systems and even sewage systems
in urban and rural areas. Most important problem of suffered people is how to get water for their drinking/cooking
and toilet cleaning in the emergency. In same cases, water for the fire fighting is the most urgently necessary one
because often the hydrant does not work well in an earthquake emergency. Medical activities are also damaged
largely by destroying water supply system at the earthquake. Securing water for daily life in the earthquake
emergency as well as in the case of drought caused by the extreme climate must be a crucial problem and the
establishment of countermeasures for those is one of our concerned issues, especially in a Mega City like Tokyo.
Objective:
The purpose of the paper is to describe an example of groundwater use in earthquake emergencies,
which is launching by Japanese local governments after the huge Awaji-Hanshin (Kobe) earthquake (M7.3)
occurred in 1995, as one of countermeasures for the secure of water in the earthquake
emergency.
Methods:
The author has searched and analyzed reports, books and news papers regarding water
use problems and countermeasures for the secure of water in the Kobe earthquake, which was the worst natural
disaster we had after the World War II, and other huge earthquakes occurred after the Kobe earthquake in Japan.
Results and conclusion:
The results indicated that groundwater is very useful water source as the domestic
water for toilet cleaning, which is one of big water use problems and needs a huge amount of water in the earthquake
emergency. Groundwater was also useful water source than river or pond waters for the fire fighting by citizen in the
case of Kobe earthquake. For the purpose of drinking and cooking, quality check of groundwater must be
necessary at the ordinary time. Hand pumps or diesel/petrol-driven pumps have to be prepared for using
groundwater in the emergency because the required electricity supply may not be available after an earthquake. It
makes clear that the registration system of citizen’s wells is launching by many Japanese local governments and
mapping of springs and wells is also proceeding by citizen for using groundwater in emergency purposes. Some
hospitals have introduced a deep well facility, which can supply 80 % of drinking water in an ordinary time, with a
membrane filtration system and a private power plant system. 353 facilities with like these systems have been
introduced in whole Japan by April 2004 including 116 hospitals. Moreover, in recently, utilization of rainwater on
the roof of households, which is led to a street furniture (water tank) with hand pump, is also spread in Ward districts
of Tokyo for the purpose in emergency. In conclusion, groundwater, which coincides with need and supply places, is
a significant water source in an earthquake emergency. For this purpose, establishment of a continuous monitoring
system of groundwater level as well as water quality at an ordinary time could be useful for an emergency resource
of groundwater.