Coasts

Dissipative beaches are characterised as being high energy beaches with a wide surf zone (300-500 m) including two to three shore normal bars and troughs, and a low-sloping and wide beach face consisting of fine sand.

Low tide terrace beaches are composed of fine to medium sand and have a moderately steep beach face joined to an attached bar or shallow terrace that is often exposed at low tide.

Bars transverse (perpendicular) to and attached to the beach separated by distinct rip troughs at 150-300 m spacing.

Rhythmic bar and beach are high energy beaches that consist of a rhythmic (undulating) bar, trough and beach.

Longshore bar and trough beaches consist of a shore parallel bar separated from the beach by a deep trough.

Reflective beaches have the lowest wave energy of the wave-dominated beaches (breakers 0-1 m high).

Coast Care provides an opportunity for local communities to get involved in the management and protection of their local coastal area and address environmental issues with their beaches.

Beach profile monitoring is usually undertaken as survey transects running shore normal from the dune to the low water mark. It provides information that can be used to assess whether a shoreline is eroding or accreting.

The coastal type classification describes the coast in terms of exposure, the type of foreshore sediment, inland and coastal geography.

NIWA's has mapped the seabed off the coast of Otago, revealing the structure of nine canyons in the Great South Basin. This survey is providing new information about geological processes in the region as well as clues to what types of life might exist on the seafloor.