PEGELONLINE (Germany)

What it is: Germany's online water-level service, with 1-minute water levels from coastal, tidal-river and inland gauges.
Publisher: Wasserstraßen- und Schifffahrtsverwaltung des Bundes (WSV).
What OTC takes: Gauge records that OTC fits. PEGELONLINE publishes no harmonic constants. It keeps only about 31 days of history, so OTC will harvest the records into its own archive and fit constants when enough data has accumulated: at least 30 days for a minimal fit, one year for a full fit.
Licence: Data licence Germany – Zero – Version 2.0 (DL-DE->Zero-2.0), with no conditions, as stated in the PEGELONLINE terms of use.
Attribution line OTC uses: “Contains data from PEGELONLINE (WSV), DL-DE->Zero-2.0.” The licence does not require it; OTC credits the source anyway.
Access and watching: Keyless REST API (version 2). A daily harvest, because older records are not kept upstream.
Coverage: The German North Sea and Baltic coasts and the tidal rivers (Elbe, Weser, Ems), plus inland gauges.
Rank: Gauge fit.