A collection of datasets from various Dutch institutions to demonstrate a Spatial Data Infrastructure built on Portolan.
Mining-law subsurface constructions (Dutch mijnbouwconstructie, BRO object EPC). These are works regulated under the Mining Act in the deep subsurface: deep boreholes (boorgaten), mine systems and salt caverns used for oil and gas, geothermal energy, and underground storage. 4,975 constructions are included. This object was added to the BRO/PDOK in October 2025.
Features: 4,975 | CRS: EPSG:4258 | License: CC0 1.0 (public domain) Source: PDOK / BRO (provider VRO). Formats: GeoParquet · PMTiles · GeoPackage (PDOK Atom).
Used in energy, geothermal and storage planning, subsurface spatial planning, and risk/permitting work. The point marks the surface location of the construction.
This collection comes from the Basisregistratie Ondergrond (BRO) — the Dutch Key Registry of the Subsurface, a statutory base registry in force since 1 January 2018. Government bodies must register subsurface data in the BRO and may only use registered data for public tasks. Data is published openly via PDOK, usually within ~1 day of registration. The Ministry of Housing and Spatial Planning (VRO) is the system-responsible provider; the data here is produced by TNO – Geologische Dienst Nederland (subsurface objects) or Wageningen Environmental Research (the soil and geomorphological maps).
Two BRO concepts appear in almost every dataset:
bro_id — the unique registration identifier of each object (e.g. GMW000000012345).quality_regime — IMBRO (full quality assurance) or IMBRO/A (transitional data delivered under a lighter regime; treat with slightly more caution).DuckDB (analytics):
GeoPandas:
Geometry is stored in standardized_location (WKB, EPSG:4258); standardized_location_bbox is a per-feature bounding-box
struct enabling fast spatial pre-filtering.
legal_status is frequently onbekend (unknown) or buitenGebruikMijnbouw (decommissioned).Geological boreholes (BHR-G), GeoTOP / DGM subsurface models.
Column names in this collection are the English BRO field names. Common Dutch equivalents:
bronhouder = delivery_accountable_party (data owner), kwaliteitsregime = quality_regime, bodemklasse = soil class, hoofdklasse = main soil class, genese = genesis (landform origin), reliëf = relief, boring/booronderzoek = borehole, sondering = cone penetration test, grondwater = groundwater, mijnbouw = mining, bodemverontreiniging = soil contamination.
Mapbox GL v8 style files (use with MapLibre GL JS, OpenLayers via ol-mapbox-style, or any Mapbox GL v8 renderer) live alongside the PMTiles:
styles/default.json — BRO Mining Construction (EPC / Mijnbouwconstructie) — Default (https://data.source.coop/cholmes/portolan-nl/vro/mijnbouwconstructie/styles/default.json)styles/by-legal-status.json — BRO Mining Construction (EPC / Mijnbouwconstructie) — By legal status (https://data.source.coop/cholmes/portolan-nl/vro/mijnbouwconstructie/styles/by-legal-status.json)mijnbouwconstructie.pmtilesvia links in
collection.json.Part of the Portolan NL catalog · CC0 1.0 · provider VRO (Ministerie van Volkshuisvesting en Ruimtelijke Ordening).
| string |
| Whether a coordinate/height transformation was applied (ja/nee). |
standardized_location | binary | Object location — WKB geometry in EPSG:4258 (ETRS89). |
standardized_location_bbox | struct<xmin: float, ymin: float, xmax: float, ymax: float> | Per-feature bounding box struct (xmin,ymin,xmax,ymax) for spatial filtering. |