Skip to main content

Methods - how we monitor

Where and how we collect the data

Monitoring sites

The coastline of the Waikato Region.

Monitoring frequency

Every 10 years.

Monitoring history

This is the second time the Waikato Regional Council has mapped the coastline ownership for the Region. The Core Record System (CRS) information used was current at June 2015. This information is purchased from Land Information New Zealand (LINZ).

 Future work could include investigating old records of coastal ownership to examine past trends.

Measurement technique

This indicator is measured solely through the use of a Geographic Information System (GIS) using the CRS data and specific GIS tools and methods.

How this indicator is compiled

The process for generating this indicator is very GIS intensive. The following steps were undertaken in the GIS:

The process for generating this indicator is very GIS intensive. The following steps were undertaken in the GIS:

  • From the Waikato Regional Council’s corporate GIS database, the shoreline (digitised from 2012 WRAPS photographs) was taken and split into three main regions – West Coast, West Coromandel Coast (to the point west of Port Jackson) and the East Coromandel Coast.
  • A 100 m merged buffer was generated for each coastal region.
  • For each coastal region:
    • Cadastral parcels from the CRS were found that intercepted or ‘touched’ the 100 m buffer around the coast. These are the coastal parcels.
    • Possible unique values for the PURPOSE_1 field of the CRS were analysed and grouped into publicly owned and privately owned.
    • The coastal parcels were then split into these groupings and merged based on this attribute.
    • The CRS_road GIS layer was also used to determine if a road edge met the coastline and this was attributed as a road edge.
  • These parcel groupings were then used to split and attribute the coastline as either private, public or road.
  • Once the three coastal regions had been captured with respect to public, private or road edge, the length of each segment was calculated using the GIS tools.

Guidelines and standards

None relevant to this indicator.


The first dataset of coastal ownership (2002) was calculated using the shoreline derived from the 1:50,000 topographic dataset (the NZMS260 series map sheets). This shoreline was not always accurate, particularly in undeveloped areas on the West Coast. The latest update (2015) has utilised a recently completed shoreline that was mapped using 2012 orthorectified photographs and Lidar data.  During data analysis it became clear that there will be some considerable differences in the 2012 output when compared with 2002, due simply to the differences in the mapped shoreline and the CRS. Any reporting of these differences would be misleading. This indicator therefore reports just the results of the most recent ownership analysis.

The reporting of "road" is based on road reserve parcels in the CRS. In some cases these areas are not formed roads.

This indicator has been compiled using the 2012 shoreline digitised from recent aerial photography and Lidar data.  The definition of coastal ownership relates to the parcel ownership where it is intercepted by the 2012 shoreline. Therefore historical public reserves that have been eroded and are now seaward of the current shoreline are not included and the shoreline in these areas is classified as privately owned.

It is important to remember that this indicator measures shoreline ownership based on the ownership of the land directly adjacent to the shoreline, and is not a direct measure of shoreline accessibility. For example, in some areas, publicly owned reserve strips (e.g. road reserves) exist on the coastal margin in areas where they are disconnected from any road or pedestrian access. There are also areas of publicly owned land that are currently leased to private parties (e.g. forestry), so are not currently freely accessible to the public, but the potential remains for these areas to be made public in the future.

Further indicator developments

No changes are planned for this indicator.

Quality control procedures

The ownership data is sourced from the individual Territorial Authorities. The Waikato Regional Council does not maintain, update or amend any ownership details. However when errors are spotted, business processes are in place to raise these with the appropriate Territorial Authorities and their Valuation Service Provider (VSP) for correction.

The merging of the CRS and ownerhip data is a simple database join exercise. The relationship files used to match the CRS parcels to property valuation are created and maintained by Waikato Regional Council.