Darfield; south-southeast of Westport; south-west of Wellington; and north-northeast of Dunedin. Sewers were damaged, gas and water lines were broken, and power to up to 75% of the city was disrupted. Among the facilities impacted by lack of power was the Christchurch Hospital, which was forced to use emergency generators in the immediate aftermath of the quake. A local state of emergency was declared at 10:16 am on 4 September for the city, and evacuations of parts were planned to begin later in the day. People inside the Christchurch city centre were evacuated, and the city's central business district remained closed until 5 September . A curfew from 7 pm on 4 September to 7 am on 5 September was put in place. The New Zealand Army was also deployed to assist police and enforce the curfew. All schools were closed until 8 September so they could be checked. Christchurch International Airport was closed following the earthquake and flights in and out of it cancelled. It reopened at 1:30 pm following inspection of the main runway. The earthquake was reported to have caused widespread damage and power outages. 63 aftershocks were also reported in the first 48 hours with three registering 5.2 magnitude. Christchurch residents reported chimneys falling in through roofs, cracked ceilings and collapsed brick walls. The total insurance costs of this event were estimated to reach up to $11 billion according to the New Zealand Treasury. February 2011 A large aftershock of magnitude 6.3 occurred on at 12:51 pm. It was centred just to the north of Lyttelton, 10 kilometres south east of Christchurch, at a depth of 5 km. Although lower on the moment magnitude scale than the quake of September 2010, the intensity and violence of the ground shaking was measured to be VIII (Severe'') on the Mercalli intensity scale and was among the strongest ever recorded globally in an urban area due to the shallowness and proximity of the epicentre. Early assessments indicated that approximately one third of buildings in the Central Business District would have to be demolished. In contrast to the September 2010 quake, the quake struck on a busy weekday afternoon. This, along with the strength of the quakes, and proximity to the city center resulted in the February earthquake causing the tragic deaths of 181 people. This event promptly resulted in the declaration of New Zealand's first National State of Emergency.