Water authority structures by type: most culverts (626,955 objects), then bridges and fixed dams

Water authority structures by type, October 2026, in objects. Total: 956,399; the largest 12 of 18 categories are shown. Culverts is 66% of the total. Each type is a separate layer; counted per layer with resultType=hits.

Source: Het Waterschapshuis, Waterschappen Kunstwerken IMWA via PDOK (WFS) · opgehaald 25 oktober 2026Open the table Single block

These figures come from

Water authority data (IMWA and DAMO)

Het Waterschapshuis

Six map services from Het Waterschapshuis with the assets of all 21 Dutch water authorities in one national model (IMWA): structures such as pumping stations, weirs, locks and culverts, flood defences and how they are built, surface water, water level areas, protection zones and the wastewater chain (sewage pumping stations, treatment plants, pipes). On 16 October 2026 it held 8,566 pumping stations, 53,137 weirs, 626,869 culverts, 37,419 water level areas and 317 wastewater treatment plants. Every object names its water authority. Via PDOK as OGC API, and for five of the six also as WFS and WMS.

This block is an example of what you can show with this source. Open the source itself to look further, pick other figures or use the data in your own work.

Open the table at Het Waterschapshuis The API call behind this block All about this source

Access: Open
Licence: Gemengd: CC0 1.0 (keringen, oppervlaktewateren), CC BY-SA 4.0 (kunstwerken, waterbeheergebieden, zoneringen, waterketen DAMO)
Table: waterschappen-kunstwerken-imwa
Latest figure: oktober 2026
Fetched: 25 October 2026

Fetch exactly these figures yourself

curl "https://service.pdok.nl/hwh/waterschappen-kunstwerken-imwa/wfs/v2_0?service=WFS&version=2.0.0&request=GetFeature&resultType=hits&typeNames=duiker"

curl "https://service.pdok.nl/hwh/waterschappen-kunstwerken-imwa/wfs/v2_0?service=WFS&version=2.0.0&request=GetFeature&resultType=hits&typeNames=gemaal"

Water authority structures by type: most culverts (626,955 objects), then bridges and fixed dams

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