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Geographic Area: Porirua metropolitan area, including Plimmerton, Mana, Paremata, Pauatahanui, Titahi Bay, Porirua City, and Tawa. 

Summary: This booklet supports the accompanying liquefaction hazard map sheets for the Porirua area, which identify zones of liquefaction potential and liquefaction induced ground damage under two earthquake scenarios. The maps are compiled using geological data, ground shaking assessments, and historical records. The booklet is structured into eight parts: background information, map descriptions, types of ground damage, assessment methodology, limitations, data sources, earthquake scenarios, and geology and ground conditions across seven subareas.  

Section 3.5 discusses the liquefaction potential across the Porirua area. Most locations in Porirua show potential for liquefaction under Scenario 1, except Titahi Bay, which has marginal resistance. Elsdon and Mungavin areas also show marginal potential. Under Scenario 2, all susceptible soil layers are expected to liquefy. These findings help inform planning and development by identifying areas at risk of ground damage during seismic events.