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This study focuses on topographic hollows, their flow direction and flow accumulation characteristics, and highlights discharge of hillslope seepage so as to understand porewater pressure development phenomena in relation with slope failure in topographic hollows. For this purpose, a small catchment in Niihama city of Shikoku Island in western Japan, with a record of seven slope failures triggered by typhoon-caused heavy rainfall on 19–20 October 2004, was selected. After extensive fieldwork and computation of hydro-mechanical parameters in unsaturated and saturated conditions through a series of laboratory experiments, seepage and slope stability modellings of these slope failures were done in GeoStudio environment using the precipitation data of 19–20 October 2004. The results of seepage modelling showed that the porewater pressure was rapid transient in silty sand, and the maximum porewater pressure measured in an area close to the base of topographic hollows was found to be higher with bigger topographic hollows. Furthermore, a threshold relationship between the topographic hollow area and maximum porewater pressure in this study indicates that a topographic hollow of 1000 sq. m area can develop maximum porewater pressure of 1.253 kPa. However, the porewater pressures required to initiate slope instability in the upper part of the topographic hollows is relatively smaller than those in the lower part of the topographic hollows. [ABSTRACT FROM PUBLISHER]

In this work, we prepare and replicate a deterministic slope failure hazard model in small-scale catchments of tertiary sedimentary terrain of Niihama city in western Japan. It is generally difficult to replicate a deterministic model from one catchment to another due to lack of exactly similar geo-mechanical and hydrological parameters. To overcome this problem, discriminant function modelling was done with the deterministic slope failure hazard model and the DEM-based causal factors of slope failure, which yielded an empirical parametric relationship or a discriminant function equation. This parametric relationship was used to predict the slope failure hazard index in a total of 40 target catchments in the study area. From ROC plots, the prediction rate between 0.719–0.814 and 0.704–0.805 was obtained with inventories of September and October slope failures, respectively. This means September slope failures were better predicted than October slope failures by approximately 1%. The results show that the prediction of the slope failure hazard index is possible, even in a small catchment scale, in similar geophysical settings. Moreover, the replication of the deterministic model through discriminant function modelling was found to be successful in predicting typhoon rainfall-induced slope failures with moderate to good accuracy without any use of geo-mechanical and hydrological parameters. [ABSTRACT FROM PUBLISHER]

Earthquakesare one of the most significant natural hazards in Nepal and there is a long history of destructive earthquakes in the region. Despite the risk of earthquake disasters, however, school construction practice in Nepal has largely ignored the issues of structural safety. Most schools are built without following proper design guidelines. As an effective tool to reduce earthquake disaster risk in the public schools of Nepal, the Public School Earthquake Safety Program was recently initiated in Nepal. In this program, more than 1000 public schools from six districts of Nepal were evaluated for earthquake safety, and various awareness raising and retrofitting programs were implemented. This paper describes the program features, extent of community participation, retrofitting processes and lessons learned while implementing the earthquake safety program. It also demonstrates how school earthquake safety programs ultimately increase the seismic safety of the entire community in the Himalayan regions. [ABSTRACT FROM AUTHOR]

Because of extreme vulnerability to natural disasters, Nepal is considered a disaster hotspot in the world. For a small country with just a little less than 30-million population, the disaster statistics are always frightening. School students of Nepal are also in extreme risk of natural disasters, especially when they are in schools. In this context, a few education programmes for disaster risk reduction (DRR) have already been initiated and the results have also been already documented. However, an evaluation of the real scenario with the help of an independent research is still lacking. Therefore, this research aims to explore benefits of existing education programmes of DRR in Nepal. Altogether, 124 students from 17 districts were interviewed and various questions related to disaster information, disaster knowledge, disaster readiness, disaster awareness, disaster adaptation, and disaster risk perception were asked. Statistical analysis such as histogram analysis, distribution analysis, bivariate correlations, and independent samplet-tests were conducted to examine the relationship between students in disaster education-related programmes and the key DRR issues-related dependent variables. Findings of this independent research confirmed that initiatives taken for disaster education in Nepal are not enough and a major challenge for DRR in a school community for a country like Nepal is implementing methods, especially at the individual level. Likewise, the disaster education should not only be confined within the school students, but it must also be promoted to families and communities, which is very essential to elaborate knowledge of DRR and to contribute to a disaster safe society in the country. [ABSTRACT FROM PUBLISHER]