{"id":"finland-river-discharge","slug":"finland-river-discharge","name":"Finland Historical River Discharge Dataset","description":"Daily river discharge for the Finnish national hydrological network, from the nineteenth century to the present: 671 gauging stations across 62 main drainage basins, taken exactly as the Finnish Environment Institute publishes it. It holds the single deepest continuous daily record on the platform.","methodology":"Collected from the Syke Hydrologiarajapinta OData service under CC BY 4.0, with no key and no registration. Values are stored as Syke publishes them and are not recomputed: Syke derives each daily discharge from its own measurement and rating curves, and a mean recalculated by Hydrionis would be a different statistic under the same name. Syke carries a per-value quality flag; values flagged as possibly erroneous are refused, because Hydrionis cannot show a per-point flag on a chart and a doubted value plotted beside a trusted one is indistinguishable from it. Interpolated values are stored and described on the series, on the reasoning that interpolation is a stated method rather than a doubt and that removing it would punch holes in the middle of continuous records. Station coordinates are published as degrees-minutes-seconds integers and are converted; read as decimal degrees they would place Finnish gauges in the Indian Ocean.","domains":["river-flow"],"metricIds":["river-flow-mean"],"subjectScope":"Finnish hydrological gauging stations reporting discharge","cadence":"daily","version":"1.0.0","released":"2026-08-26","changelog":[{"version":"1.0.0","date":"2026-08-26","summary":"First release. Finland becomes the largest single archive on the platform by measured days.","additions":["Daily discharge for 671 stations across 62 main drainage basins.","Main drainage basin name and official code carried onto every station, so Finnish gauges join the water graph as they are collected rather than through a separate linkage pass."]}],"limitations":["Discharge is a property of a gauging station and its reach, not of a river. Two stations on the same watercourse routinely differ by an order of magnitude, and no figure here describes a river as a whole.","Finnish rivers are extensively regulated for hydropower and for lake level management. Discharge at a regulated station reflects operating decisions as much as hydrology, and Syke does not publish a regulation flag through this interface, so Hydrionis cannot mark which stations are affected.","A small number of values carry an interpolation flag and are stored as such. They are a stated method rather than a measurement, and each series says how many it holds.","Values Syke itself flags as possibly erroneous are absent. That is a deliberate refusal rather than a gap in the publisher’s archive, and a reader reconstructing Syke’s own record should go to Syke.","Forty stations in the network hold fewer than a year of usable days and are absent. Most are short-lived or very recently opened."],"observationCount":10342715,"seriesCount":672,"subjectCount":672,"from":1847,"to":2026,"sourceIds":["fi-syke-hydrologia"],"units":["m³/s"],"redistributable":true,"commerciallyReusable":true,"citation":"Hydrionis (2026), Finland Historical River Discharge Dataset, version 1.0.0. Retrieved from https://hydrionis.com/data/datasets/finland-river-discharge/","downloads":[{"file":"/downloads/observations-river-flow-fi-syke-hydrologia.csv","format":"CSV","label":"river-flow observations from Syke, part 1 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part2.csv","format":"CSV","label":"river-flow observations from Syke, part 2 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part3.csv","format":"CSV","label":"river-flow observations from Syke, part 3 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part4.csv","format":"CSV","label":"river-flow observations from Syke, part 4 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part5.csv","format":"CSV","label":"river-flow observations from Syke, part 5 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part6.csv","format":"CSV","label":"river-flow observations from Syke, part 6 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part7.csv","format":"CSV","label":"river-flow observations from Syke, part 7 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part8.csv","format":"CSV","label":"river-flow observations from Syke, part 8 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part9.csv","format":"CSV","label":"river-flow observations from Syke, part 9 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part10.csv","format":"CSV","label":"river-flow observations from Syke, part 10 of 11 (1,000,000 rows)"},{"file":"/downloads/observations-river-flow-fi-syke-hydrologia-part11.csv","format":"CSV","label":"river-flow observations from Syke, part 11 of 11 (375,908 rows)"}],"apiPath":"/api/v1/datasets/finland-river-discharge.json","lastFetched":"2026-10-01","fields":[{"id":"river-flow-mean","name":"Mean river flow","definition":"Average volumetric discharge past a gauging station over a stated period.","unit":"m³/s","nativeGeography":["river-gauge"],"comparabilityNotes":"Flow is a property of a specific gauge on a specific reach, and cannot be attributed to a river as a whole. Two gauges on the same river can differ by an order of magnitude. Where a station measures flow through a sluice, lock or pumping station — much of the Dutch network does — discharge is signed and a negative value means water moving in the reverse direction, which is a real operating state and not an error. Managed flow of that kind is not comparable with discharge at a natural gauging station, because it reflects operational decisions as well as hydrology."}]}