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Geographic Area: Wairarapa area, including Masterton, Carterton, Greytown, Featherston, and Martinborough 

Summary: This booklet supports the liquefaction hazard assessment for the Wairarapa are and complements regional seismic hazard mapping. Unlike other areas, the Wairarapa hazard is summarized in booklet form only, without accompanying map sheets. The booklet is structured into seven parts: Part 1 provides background; Part 2 outlines types of ground damage; Part 3 explains liquefaction assessment methodology; Part 4 discusses limitations; Part 5 summarizes data sources; Part 6 defines earthquake scenarios; and Part 7 describes geology and ground conditions. 

 Section 3.5 discusses historical evidence of liquefaction in the Wairarapa, including reports from the 1855 and 1942 earthquakes. Some observations confirm liquefaction, while others suggest related ground movement. The assessment concludes that soils in the Wairarapa are generally resistant to liquefaction during a moderate earthquake (Scenario 1), but may have marginal potential during a severe earthquake (Scenario 2). Liquefaction hazard is considered higher in areas outside the study region, particularly to the east and south where loose sand and silt sediments are present. The booklet provides regional-scale information to support planning and risk mitigation, noting that site-specific investigations are necessary for development decisions.