canonical: https://jentic.com/apis/oppervlaktewaterlich/oppervlaktewaterlich # Oppervlaktewaterlich Oppervlaktewaterlichamen Jentic publishes the only available OpenAPI specification for Oppervlaktewaterlichamen, keeping it validated and agent-ready. The Oppervlaktewaterlichamen service published by PDOK provides the spatial dataset of Dutch surface water bodies used as the basis for the EU Water Framework Directive (Kaderrichtlijn Water) inside the Rijkswaterstaat management area. Agents can pull a feature collection of either lijnen (lines) or vlakken (polygons), or fetch a single feature by ID, returning GeoJSON-style geometries with administrative metadata. The service is anonymous and intended for read-only spatial queries. ## For AI agents Look up Dutch surface water bodies (rivers, canals, lakes) as polygon and line features for environmental and GIS workflows, with no authentication required. ## Scope Does not handle water quality measurements, flow data, geocoding, or routing - use for retrieving Dutch surface water body polygons and lines only. ## Capabilities - List every surface water body polygon (vlakken) in the Rijkswaterstaat management area - Retrieve a single water body polygon by its feature ID with full geometry - List every surface water body line feature (lijnen) for the network - Retrieve a single line feature by ID for use in routing and overlay maps - Filter feature collections by spatial extent and pagination parameters ## Use cases ### Environmental compliance reporting Environmental consultants preparing Water Framework Directive reports can pull the canonical polygon set from /vlakken to ensure their analyses align with the Rijkswaterstaat reference geometries. Because the dataset is the spatial basis of KRW reporting in the Netherlands, using the same source removes alignment errors when overlaying water quality measurements onto water bodies. Example prompt: GET /vlakken with a bounding box for the project area and store the returned polygons as GeoJSON for the compliance report. ### Map overlays for GIS dashboards GIS teams building public dashboards can render Dutch water bodies as either polygon fills or thin centrelines by mixing the /vlakken and /lijnen endpoints. The line endpoint is well suited to background reference layers on small-scale maps where polygon detail would create visual noise. Example prompt: GET /lijnen for a viewport and serve the response as a vector tile layer in the GIS dashboard. ### Spatial joins with monitoring data Researchers can pair point measurements (water quality, flow, ecology) with the polygon set from /vlakken to assign each measurement to its host water body. A single polygon retrieved by ID via `/vlakken/{id}` provides enough geometry for client-side point-in-polygon tests without downloading the entire collection. Example prompt: GET `/vlakken/{id}` for each candidate water body and run a point-in-polygon test against the measurement coordinate. ### AI agent for Dutch water data Through Jentic, an environmental research agent can answer 'show me the geometry of the Hollandsche IJssel' by searching for the right operation, calling /vlakken with a name filter (or scanning lijnen for matching identifiers), and returning GeoJSON the user can drop into QGIS or a Leaflet map. No credentials are needed. Example prompt: Search Jentic for 'list pdok surface water polygons' and execute /vlakken, returning the matching feature for the named water body. ## Key endpoints | Method | Path | Description | | --- | --- | --- | | GET | `/vlakken` | List water body polygon features | | GET | `/vlakken/{id}` | Get a single polygon feature by ID | | GET | `/lijnen` | List water body line features | | GET | `/lijnen/{id}` | Get a single line feature by ID | ## Key resources - **Vlakken** — Surface water body polygons with geometry and metadata - **Lijnen** — Surface water body line features for rivers and canals ## Why Jentic - **Setup:** Wiring the Oppervlaktewaterlichamen service by hand means constructing its polygon and line feature queries and paging the results yourself. Through Jentic you install once, import the Oppervlaktewaterlichamen API from the API Directory, and your agent calls it directly. - **Permission scoping:** This service puts the feature id in the URL path (`/vlakken/{id}`, `/lijnen/{id}`), so a rule can pin your agent to reading one water-body feature. You choose the operations it may call, so the collection listings are not included unless you add them, and it stays read-only either way. - **Credential handling:** The service is anonymous, so nothing secret is stored for this API. Jentic still wraps each call in its audited execution path, and no credential ever enters the agent's prompt, logs, or context. - **Discovery method:** Agents search Jentic by intent such as 'list dutch surface water polygons', and Jentic returns the matching /vlakken or /lijnen operation with its parameter schema so the agent calls the right endpoint without browsing the reference docs. ## Related APIs - **PDOK Habitatrichtlijn Habitat Types WFS** — Sister PDOK service publishing EU Habitats Directive features - **PDOK Locatieserver** — PDOK's geocoding and place-search service for Dutch addresses - **PDOK Oppervlaktewaterlichamen (alternative endpoint)** — Parallel PDOK publication of the same surface water dataset ## FAQ ### Why is there no official OpenAPI spec for Oppervlaktewaterlichamen? PDOK does not publish an OpenAPI specification for this service. Jentic generates and maintains this spec so that AI agents and developers can call Oppervlaktewaterlichamen via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer. ### What authentication does the Oppervlaktewaterlichamen API use? The service is open and requires no authentication. Through Jentic the operations are still wrapped in the standard execution flow, but no vaulted credential is needed for these four endpoints. ### Can I retrieve a specific water body by name with this API? Not directly. The /vlakken and /lijnen endpoints return feature collections that include attributes such as the water body name; agents typically list features inside a bounding box and filter client-side, or call `/vlakken/{id}` when the feature ID is already known. ### What are the rate limits for the Oppervlaktewaterlichamen API? PDOK applies fair-use limits to its public services rather than per-key quotas. Treat 429 responses with backoff and avoid downloading the full national collection in a single request - use spatial filters where possible. ### How do I find every water body polygon inside a region through Jentic? Search Jentic for 'list pdok surface water polygons', load the GET /vlakken operation, and pass a bounding box that frames the region. The response is a GeoJSON-style feature collection ready for use in QGIS or Leaflet. ### Is the Oppervlaktewaterlichamen API free? Yes. PDOK publishes the dataset as open government data under the Netherlands national spatial-data infrastructure. There is no paid plan or usage charge. ### Can I limit what my agent is allowed to do with the Oppervlaktewaterlichamen API? Yes. Because you run Jentic One yourself, your own rules decide which of the four operations the agent may call, so you can allow only GET `/vlakken/{id}` and GET `/lijnen/{id}` to pin it to reading a single water-body feature while leaving the /vlakken and /lijnen collection listings out. Since the feature ID sits in the URL path, a rule can scope the agent to one specific feature rather than the whole national dataset. Every operation is read-only, so the agent can retrieve polygon and line geometry but never modify anything.