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8. Landslide Research in IrelandThis chapter attempts to document the landslide research which has been undertaken in Ireland. It is by nomeans an exhaustive review of the work that has been done. Prior to 2003, when the Pollatomish and Derrybrienlandslides occurred, research work on landslides can be divided into two categories. The first was field basedgeomorphological study carried out by geology and geography academics, and the second was geotechnicaland largely laboratory based research done in civil engineering departments of the universities. Tomlinson(Queens University, Belfast) worked on peat erosion and peat slides in the uplands of Northern Ireland. Coxon(Trinity College Dublin), with other colleagues, documented the peat slides in Co. Sligo during the 1980’s.Dykes, Kirk, and Warburton examined peat failures on Cuilcagh Mountain on the Cavan/Fermanagh border.Hanrahan and others worked extensively on the geotechnical properties of peat.Subsequent to the landslides of 2003 and the establishment of the Irish Landslides Working Group, a researchworkshop was held in Trinity College Dublin in October 2004. This brought together several university lecturersand postgraduate students who were working on various aspects of landslides research in Ireland. Abstracts ofthese and other research projects are included in this publication. There are two abstracts on the Pollatomishlandslides. Dykes and Warburton documented the landslides and discussed the reasons for peat failure.Murphy conducted a geophysical investigation on one slide using ground penetrating radar (GPR) and aseismogram. The GPR successfully determined the failure plane of the peat. O’Loinsigh and Boylan examinedthe use of satellite imagery and digital elevation models (DEM) to identify landslide events in Co. Sligo and Co.Wicklow respectively. Colgan assessed the use of GIS techniques in mapping landslides and producingsusceptibility maps. Boylan, Long, and Farrell looked at the geotechnical properties of peat and glacial till.Elliot described submarine slope failure in offshore Ireland using data derived from the GSI National SeabedSurvey. McDonagh assessed the socio-economic significance of landslides, and Tonry addressed the issue ofthe integration of the landslide issue into the Irish planning process.Much research still needs to be done on landslides in an Irish context. From a geotechnical standpoint, peatstrength and behaviour, as well as the behaviour of Ireland’s glacially-derived soils require more work. As thework of the Irish Landslides Working Group has identified, there is a need for multi-disciplinary studies onlandslide phenomena involving geologists, geomorphologists, engineers, ecologists, climatologists, and planners.An important topic is the impact of climatic change on landslide susceptibility. With progress in these specificresearch themes, more informed research can be undertaken on the methodology of landslide susceptibilitymapping and risk assessment. All of this research requires a dedicated funding stream with the Irish LandslidesWorking Group or its successor taking up a co-ordinating or advisory role.9. Recommendations for Future WorkThe Irish Landslides Working Group recommends that a large body of research be completed with regard tolandslide hazard assessment in Ireland. The growing pressure for development in more marginal land areas,and the potential impacts of climate change, make such work an important imperative in the context of thesustainable development of the Irish landscape, and also on health and safety grounds.Landslide hazard is a major geohazard and is included as a survey and research theme in the GeoscienceInitiative recently prepared by the Geological Survey of Ireland, and currently being proposed to Government forfunding. In addition landslides are being examined in an all-Ireland context. There has been extensive cooperationbetween the Geological Survey of Ireland and the Geological Survey of Northern Ireland on this andother geoscience themes. The work will require a multi-disciplinary team bringing together various types ofexpertise, and therefore a multi-agency approach. This landslides report lays the foundation of such research,in documenting the issues involved.Several key recommendations for future work on landslides in Ireland have been made. For each project, themain objectives are set out and estimated costs given to reflect a three-year programme in all cases. Thespecific tasks for each of these objectives are also listed in the report. A strategic framework to implement thiswork programme is also outlined.1. Public Awareness/OutreachIt is important that there is much greater public awareness of landslide hazard in Ireland so that the generalpublic know of the potential for slope instability in certain areas and the possible consequences in terms of lifeand property.vi