Porirua faces various natural hazards including earthquakes, tsunami, storms, flooding and landslides. Porirua Stream and Horokiwi Stream run through the city and the Porirua coast and area surrounding the Porirua Harbour are at risk from tsunami.
Porirua City sits on the western side of the Wellington region and is largely formed around the arms of the Porirua Harbour. Porirua is home to around 56,559 people and most densely populated areas are coastal. There are two iwi within Porirua; Muaūpoko and Ngāti Toa Rangatira.