NZ SPI Adjustments

This layer provides the extents of the data incorporated into an adjustment which has been completed as part of the Spatial Parcel Improvement (SPI) project. The SPI project aims to improve the accuracy of digital cadastral data in areas (primarily rural) where survey-accurate data does not currently exist. The improvement of coordinates is controlled by a mathematical adjustment process using a Least Squares methodology. The adjustment/integration process results in increased mapping accuracy of surrounding spatial objects (e.g. parcels), the effect of which is some new observations or parcels appear to move. The extent of the change largely depends upon the accuracy of the underlying data. In general, movements will be at least several metres, as the SPI project targets areas where significant movements are expected.