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Geographic area covered: Wellington City, Hutt Valley, Porirua Basin, Kāpiti Coast, and Wairarapa. 

This report reviews historical records of earthquake-induced liquefaction across the Wellington Region, focusing on five sub-areas: Wellington City, Hutt Valley, Porirua Basin, Kāpiti Coast, and Wairarapa. It draws on newspaper archives, government reports, and personal accounts to identify ground damage consistent with liquefaction, such as sand boils, ground fissures, subsidence, and lateral spreading. The study concentrates on earthquakes of Modified Mercalli intensity VII or greater, particularly the 1848 Marlborough, 1855 Wairarapa, and 1942 Masterton events. 
 
In Wellington City, liquefaction was observed during the 1855 earthquake, with reports of mud ejection and fissures near Willis and Manners Streets. Reclaimed land along the waterfront showed signs of subsidence and cracking during the 1942 earthquakes. In the Hutt Valley, sand boils and fissures were reported in the lower valley in 1855, and subsidence near bridge abutments occurred in 1942. Porirua Basin had limited historical records, but one 1855 account noted road subsidence. On the Kāpiti Coast, fissures and gas-emitting holes were observed near Waikanae in 1848, and railway subsidence was reported in 1942. In the Wairarapa, liquefaction was documented near Pahautea and along riverbanks during the 1855 and 1942 events. 
 
The report concludes that liquefaction has occurred in the region during past earthquakes and is likely to recur. It highlights that areas underlain by recent alluvial, marine, or swamp deposits are most susceptible. The authors note that historical records may underrepresent liquefaction due to sparse settlement and limited documentation. They recommend further investigation of susceptible areas, especially where development has occurred on reclaimed or unconsolidated ground. The findings support the need for land use planning and hazard mitigation strategies that account for liquefaction risk.