A collection of datasets from various Dutch institutions to demonstrate a Spatial Data Infrastructure built on Portolan.
A spatial reference grid of 3,112 hectometer sections (hectometervakken) along the fairway (vaargeul) of the Rhine branches in the Netherlands. Each polygon represents a section of the navigable channel, identified by a section ID.
This is primarily a spatial indexing grid — it provides the spatial framework for referencing locations along the Rhine waterways. The attribute data is minimal; the value lies in the spatial geometry itself.
Provider: Rijkswaterstaat (Directorate-General for Public Works and Water Management) License: Public domain (Dutch government open data)
The data is a GeoParquet file in EPSG:28992 (Amersfoort / RD New). Use DuckDB with the spatial extension.
The vak_ID prefix identifies the waterway. Extract it to group sections.
One Mapbox GL v8 style is available for interactive map visualization via the PMTiles file.
Style files are Mapbox GL v8 JSON with relative PMTiles source paths. They can be used with MapLibre GL JS, OpenLayers (via ol-mapbox-style), or any Mapbox GL v8-compatible renderer.
styles/default.json — Dark navy blue fill with darker outlines. Shows fairway channel sections along major Dutch waterways. Navigational-chart appearance.Style files are at: https://data.source.coop/cholmes/portolan-nl/rijkswaterstaat/hectometervakken_vaargeul/styles/
vak_ID for cross-referencing with other Rijkswaterstaat
datasets (e.g., depth measurements, water quality).vak_ID prefix encodes the waterway branch but the exact mapping (e.g., ij = IJssel,
wa = Waal) is not included in the dataset.Shape__Area uses double underscores (ArcGIS convention).Hand-maintained agent guide (ported from this collection's llms.txt in August 2026). Update it alongside collection.json.