 Complete the following phrase:  Lower Hutt, Napier, Wanganui, and the former Waitakere City area of Auckland each have a network of civil defense sirens. The networks in Lower Hutt and Napier are bolstered by fire sirens that also function as civil defense sirens. Lower Hutts network is further bolstered by selected industrial sirens that double as civil defence sirens. In the western Bay of Plenty, several fire sirens also serve as civil defense sirens, and there are dedicated civil defense sirens at the Bay Park Raceway in Mount Maunganui, Tokoroa, and Whangamata which has two. Additionally, Tokoroa, Putaruru, Tirau, and Whangamata have fire sirens serving double duty as civil defense sirens. In the years following the tsunamis of the 