NZ Beach Type Classification
The NZ beach type classification groups New Zealand beaches into 14 beach types based on the Wright Short model. The beach types are products of the wave, tide and beach morphology and sediment characteristics. There is a beach hazard rating associated with each beach type for modal (most commonly occurring) wave conditions. The beach hazard rating takes into account hazards such as rips, surf zone currents, deep water nearshore and how changing breaker high effects the hazard rating for each beach type.
Currently 270 NZ beaches have been classified by their beach type and assigned a hazard rating. This information can be viewed as beach report cards on Coastal Explorer.
Data scope
The beach type database has been developed through site visits to numerous beaches throughout New Zealand supplemented with information from aerial photographs.
A collaborative project with Prof Andy Short of the University of Sydney capitalises on his 17 year effort mapping, classifying and applying hazard ratings to 10,685 Australian beaches.
Mapping methodology
The classification and mapping of beach types involved identifying modal wave conditions (breaker height), tide range and beach morphology (the configuration of sand bars, and rip channels, beach slope) and sediment characteristics (grain size).
A beach hazards assessement was also conducted during site visits. It identified hazards such as rip currents, submerged rocks, stream mouths, along with features that influence the level of risk associated with the hazards such as access to the beach via tracks or road and facilites at the beach such as Surf Life Saving Clubs.
The database was assembled through literature research, examination of aerial photographs of the beaches, and on site mapping my the study team. In addition mapping undertaken of additional beaches by Surf Life Saving New Zealand was assimilated into the database.