introduction.rst

Introduction

Purpose

This document provides detailed metadata (data dictionary) for the NZ Facilities data published on the LINZ Data Service: https://data.linz.govt.nz/layer/105588

Background

The NZ Facilities dataset described here has been used to enrich the attributes for the existing NZ Building Outlines, as well as provides additional open data for various stakeholders to map risk modelling, environmental assessment, urban development, resilience planning in addition to the visualization and physical location of facilities and the buildings within them.

Prior to publishing the NZ Facilities dataset, the NZ Building Outlines dataset contained name and use attributes of only supermarkets. The NZ Facilities dataset containing hospital and school facilities was used to help add hospital and school names and uses to the building outlines dataset.

Description

The NZ Facilities dataset represents boundaries of facilities, currently hospitals and schools, within mainland New Zealand containing data from NationalMap, Ministry of Education and Ministry of Health licensed for reuse under CC BY 4.0.

A facility represents a particular activity such as a hospital or school. A facility boundary represents the extent of the land which appears to be used by a facility. A facility boundary can be different to corresponding cadastral parcel polygons because a facility can span across multiple parcels or be located in only part of a parcel. For example, a parcel owned by the Crown can include multiple schools and other facilities such as parks and reserves.

Data Creation process

NationalMap facility polygons were matched and verified against authoritative data from the Ministry of Health and the Ministry of Education. Finally the facility boundaries were used to assign names and uses to NZ Building Outlines.

Image 1. An overview of the NZ Facilities creation process, from source data to attributed facility boundaries, and finally to assigned NZ Building Outlines.

Source Data Verification

The process of verifying the NationalMap Facilities was accomplished by first matching names and locations to an authoritative point. The matches were checked for similarity of names and distance between locations. Those with disimilar names, or large distances, were investigated further and adjusted accordingly. LINZ Aerial Imagery was used to assist in manually correcting some boundary extents.

Image 2. Example of facility boundaries and authoritative source points which need to be verified.

Image 3. Example of verifying and matching names with facility locations.

Assigning Attributes

The NZ Facilities attributes are derived from the authoritative source attributes and have been standardised.

Image 4. Example of NZ Facility boundaries with verified standardised names from an authoritative source, and attributes assigned.

name

A standardised name was created by applying a consistent naming convention to the authoritative name. This standardised name was assigned to the facility boundary, for example:

source_name	name
Sacred Heart Girls' College (N Plymouth)	Sacred Heart Girls' College (New Plymouth)
TKKM o Takapau	Te Kura Kaupapa Māori o Takapau
Rudolf Steiner School (Chch)	Rudolf Steiner School (Christchurch)

source_facility_id

The authoritative source's name and identifier are assigned to the data as source_name and source_facility_id to help users link the NZ Facilities to the authoritative source data, for example:

source_name	Identifier from authoritative source	source_facility_id
Sacred Heart Girls' College (N Plymouth)	School Number 174	174
TKKM o Takapau	School Number 1142	1142
Belverdale Hospital	HPI FacId F0F065-A	F0F065-A

use

Assigned use based on the facility and provides the generic use of the facility, for example:

source_name	use
Sacred Heart Girls' College (N Plymouth)	School
Taumarunui Hospital and Family Health Team	Hospital
Belverdale Hospital	Hospital

use_type

The main categories of a facility as defined by the authoritative source, assigned to the data as use_type, for example:

source_name	Use type from authoritative source	use_type
Sacred Heart Girls' College (N Plymouth)	School Type Secondary (Year 7-15)	Secondary (Year 7-15)
Sacred Heart School (Dunedin)	School Type Contributing	Contributing
Taumarunui Hospital and Family Health Team	Certification Service Type Public Hospital	Public Hospital
Belverdale Hospital	Certification Service Type NGO Hospital	NGO Hospital

use_subtype

The additional subcategories of a facility as defined by the authoritative source, assigned to the data as use_subtype, for example:

source_name	Use sub-type from authoritative source	use_subtype
Taumarunui Hospital and Family Health Team	Service Types Public Maternity, Medical	Maternity, Medical
Belverdale Hospital	Service Types Surgical	Surgical

estimated_occupancy

The approximate occupancy of the facility from the authoritative source, assigned to the data as the estimated_occupancy. This number may not include staff of the facility, but provides for example, the number of beds in hospitals or students in schools.

source_name	Occupancy from authoritative source	estimated_occupancy
Sacred Heart School (Dunedin)	Total School Roll 33	33
Taumarunui Hospital and Family Health Team	Total Beds 14	14
Belverdale Hospital	Total Beds 15	15

last_modified

The most recent date on which any attribute or geometry that is part of the facility was modified.

Assigning Name and Use to NZ Building Outlines

Facility boundaries in this dataset were used to apply hospital and school building names to the NZ Building Outlines dataset published on the LINZ Data Service. NZ Facilities and NZ Building Outlines were compared and any building outline whose centroid intersected with a facility boundary, was assign the name and use of that facility boundary.

Image 5. Example of using NZ Facilities boundaries to assign name and use to building outlines.

Formats

Textual data uses UTF-8 character encoding.

The source geometry of all spatial data uses NZGD2000 / New Zealand Transverse Mercator 2000 (EPSG 2193) as the spatial reference system. NZ Facilities geometries are stored as MultiPolygons.

Definitions

Term	Description
LDS	LINZ Data Service
Facility	A place of a particular activity such as a hospital or school, which is often more than one building.
Facility boundary	A boundary representing the extent of the land which appears to be used by a facility.
Building	A structure generally permanent in nature which has been constructed to meet a specific objective (e.g. housing, storage, and workplace).
Building Outlines	A building outline is a 2D representation of the roof outline of a building.