During Hurricane Sandy in October 2012 a large number of homes were damaged in New York City. The mayor created the Office of Housing Recovery Operations (HRO) to provide sustainable permanent housing to displaced families. Working with this office, Arup helped understand the number of affected houses and the nature of the damage, and then used this information to develop a range of FEMA-compliant National Flood Insurance Program (NFIP)-insurable modifications that would allow flood-prone property owners to rebuild better, stronger, and more resilient housing.
Arup’s work took a broad view of the types of damage sustained and developed model redevelopment and repair programmes for different property types. The work included identifying groups of similar properties, visiting the properties to review damage, proposing retrofit or rebuild solutions, and developing these in enough detail to allow for each solution to be priced.
The team also carried out investigations into alternative solutions used in other countries and locations and reviewed how these models could be incorporated in New York within the framework of the Federal Emergency Management Agency guidance that provides the basis for National Flood Insurance Program eligibility. This material was then used by the City in public presentations to help residents understand the work that needed to be done on their own properties to make them resilient to future storm surges.
Strong basis in GIS
Arup’s work started with extensive data management and GIS analysis. Although New York City has a very strong GIS database, PLUTO, it has not been fully field verified in every location, especially in residential areas. In the days and months immediately after Sandy, it was not clear exactly which homes had been damaged, how badly, and whether there were displaced families. Data was being provided very rapidly by field inspection teams but it was still difficult to understand the extent of the damage and its human impacts.
Arup's GIS team worked with the HRO team to identify the categories of housing types, such as ranch housing, bungalows, or multi-family residences that were affected either by Hurricane Sandy’s inundation or by the new FEMA flood plain maps. This analysis was used to understand the type and scale of work needed to bring affected homes into line with future building codes and insurance requirements. To support getting people back into sustainable, permanent housing as quickly as possible, part of our team co-located with HRO to allow the work to be done more rapidly. The collaborative team produced work in a twelve-week period that, with less direct urgency, would normally have taken a year or more.