Estimation of amplification on surface soil is very important in order to estimate detail distribution of earthquake ground motion for making hazard map or realtime damage estimation. The estimation methods are classified into geomorphologic classification and borehole data. Both has good and bad points. This problem has been an either-or choice. A new method to combine geomorphologic classification and borehole data are proposed in this paper and distribution of peak ground motion during the 2004 Niigata-Chuetsu earthquake is estimated.

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In this paper a method to install dedicated water supply system for firefighting is proposed in order to maintain firefighting water in an emergency like earthquakes. At first, the method to determine the fire hazard area and to estimate water volume required for fire extinguishing is proposed. Analyses on fire damage during the Kobe earthquake are used in this method. Furthermore, the water supply system is designed using water flow analysis considering hydraulic reliability and cost. An application to Kobe City is shown as an example at last.

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Present paper shows a method to analyze cost-effectiveness for installing the new system. In this method, comparing firefighting water required for burned area under the scenario of an earthquake with water capacities before and after the system install, the burned damage reduced by the system is estimated. This method is applied to the area in Kobe City as a case study. The result of case study shows that if the large fire following the earthquake occurs with high possibility, effectiveness of the system install can be verified.

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In the 2004 Niigataken-Chuetsu Earthquake which occurred on October 23, 2004, the seismic intensity scale 7 was recorded at Kawaguchi, Kawaguchi-machi for the first time since the introduction of seismic intensity meters in 1996. We investigated damage to buildings around the seismic intensity meter. We found many heavily damaged buildings, especially for old wooden houses. Heavily damage rate of the buildings was approximately 18%. We analyzed relationship between damage levels of buildings and structure types, usage of buildings, age of buildings, raised floors or not, tiled roofs or not and post-earthquake quick inspection, using the results of our investigation. Elastic response in the period range of 1-2 sec. which closely related to heavy building damage from the recorded strong ground motion was very large. Therefore, we confirmed correspondence of elastic response in the range of 1-2 sec. to the actual building damage.

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