HydrionisGlobal Water Intelligence
Coverage

The Hydrionis monitoring network

Every gauging station, borehole, raingauge and monitored reservoir Hydrionis holds a record for, indexed by country and by what it measures. There is deliberately no page per station.

14,395 monitoring locations10 networksfrom 1836
14,395
Monitoring locations held
22,156,531
Observations from them
10
National networks
1836
Earliest record

Networks held

NetworkLocationsMeasuresRecordObservations
England5,6114,846 sampling and rain gauges, 409 observation boreholes, 356 river gauges1836–2026709,249
United States2,6801,750 river gauges, 838 sampling and rain gauges, 92 monitored reservoirs1874–2026231,620
France1,533892 river gauges, 641 observation boreholes1900–2026930,243
Poland898898 river gauges2026–20261,625
Germany744744 river gauges2026–202625,835
Scotland712358 sampling and rain gauges, 309 river gauges, 45 observation boreholes1929–2026295,795
Sweden694694 river gauges1851–20269,507,623
Finland671671 river gauges1847–202610,327,195
Ireland450450 river gauges2025–202615,621
Netherlands402381 river gauges, 21 sampling and rain gauges2025–2025111,725

Going deeper

Each network above has a page with its map and its longest records. The England monitoring network has a fuller page with station-level detail. Station data is published through the Hydrionis datasets and the static API, and every value carries the station it was measured at.

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