The river's logbook for cruise travellers Waterlogged River Cruise Watch

Sources & method

The render-or-withhold decision, made inspectable. Every element below says who publishes it, under what terms, and what we do with it.

No climate-model projection appears in any Waterlogged output, score or claim. Only measured signals are used, and only where they have earned their place on out-of-sample hindcast.

What a number on this site can be

A Waterlogged clear-line is our own arithmetic: the gauge reading at which the published reference depth, minus the ship's draught and a fixed safety allowance, still leaves a comfortable margin. It is not an operator's decision rule and no cruise line uses it.

Not every line on this site is a clear-line, and each one says which it is where it appears. Some are the waterway authority's own published low-water reference, shown as theirs and not as our arithmetic. Some are a level we estimate from the measured record, where no maintained depth is published and we would rather read the record than guess at one. Some are a hand-set judgment, and say so in those words.

Rendered

Shown on the site, with its credit and its measurement time.

Rendered data elements
Data element Source Licence or posture Note
Current German gauge level, measurement time and 72-hour movement PEGELONLINE / WSV DL-DE/Zero 2.0 — commercial reuse and transformation permitted The core of the site. Credited voluntarily, timestamped, and flagged stale rather than quietly reused. WSV describes its downloadable readings as unverified raw data.
PEGELONLINE — German federal waterways gauge service
PEGELONLINE publisher classification (low / normal / high) PEGELONLINE / WSV DL-DE/Zero 2.0 The authority's own banding of its own reading, shown as the publisher's classification. It is never an operator policy and never a Waterlogged clear-line.
PEGELONLINE — German federal waterways gauge service
Five-lowest-years same-date panel (Kaub, Cologne, Pfelling, Hofkirchen) Verified normalized PEGELONLINE daily history, 2015–2026 DL-DE/Zero 2.0 Centimetres and measured 72-hour movements on the same calendar date, described as 'in this archive' — never as odds, chance or years that failed.
Waterlogged clear-line and centimetre gap Waterlogged arithmetic over gauge datum, reference pair and assumed draught Waterlogged's own calculation; the factual inputs keep their source posture Published only where a verified reference pair exists. Labelled with the draught assumption; never stated as an operator's requirement.
Bavarian Danube long-history validation series Bavarian GKD / Bayerisches Landesamt für Umwelt CC BY 4.0 — credit and change notice required Datenquelle: Bayerisches Landesamt für Umwelt, www.lfu.bayern.de. Rendered only with its credit and modification notice attached.
Current Budapest and Kienstock readings EuRIS Hydrometeo v3 (originators OVF and viadonau) Free API use with required attribution; both originators have granted reuse in writing Current observation only. API/Service Hydrometeo v3 incorporated from EuRIS (eurisportal.eu). Beside it stand the originators' own credits: “Quelle: viadonau” for Kienstock, and — with OVF's permission — “Országos Vízügyi Főigazgatóság (OVF) / General Directorate of Water Management” for Budapest. No archive or derived climatology is taken from viadonau.
EuRIS — European River Information Services portal
BfG 14-day water-level forecast Bundesanstalt für Gewässerkunde CC BY 4.0 Values are shown with the exact credit “Bundesanstalt für Gewässerkunde (BfG)”. A current forecast also shows its own issue date and time from the CSV header. BfG values do not feed a score or clear-line.
Official German federal 14-day water-level forecast — opens BfG
BfG six-week outlook Bundesanstalt für Gewässerkunde CC BY 4.0 Weekly means are shown with the exact credit “Bundesanstalt für Gewässerkunde (BfG)”; a current forecast also shows its own issue date and time from the CSV header. Weekly means are not turned into per-day levels or passenger chances.
Official German federal six-week outlook (weekly means) — opens BfG
Hungarian Danube daily history, medians and fitted parameters OVF archived water-level data (Budapest); hydroinfo.hu tables (Kienstock) Permission from the originator to publish, provided the content accurately reflects reality and the source is credited Waterlogged has received permission from Országos Vízügyi Főigazgatóság (OVF) / General Directorate of Water Management to publish water-level data provided the content accurately reflects reality and the source is credited. Budapest's “normal for this date” curve is a 31-day circular median of daily means over 1991–2025 taken from that archive, and its history panel and record sentence draw on the same years; all three name OVF as their source. Because the curve is worked out from the figures rather than copied from them, it states that the input data originate from the General Directorate of Water Management. Kienstock's median still comes from the hydroinfo.hu tables and viadonau's own grant, and its longer archive is still not ours to republish. Nothing here changes the Budapest need line: that band remains our own judgment rather than a measurement, and it is shown labelled as one.
hydroinfo.hu — Hungarian hydrological service (official Danube levels and notices)
Kienstock gauge values (originator viadonau) viadonau / DoRIS Reuse permitted with the credit “Quelle: viadonau” The Kienstock reading and EuRIS's forward figures for it are shown with “Quelle: viadonau” beside them. Waterlogged still takes the values through EuRIS rather than from DoRIS, and derives no history or reference mark of its own from either.
viadonau / DoRIS — Kienstock gauge page with its forward view (English)
German waterway notices ELWIS / WSV OpenData — commercial reuse only when content is unaltered and credited “www.elwis.de”; links permitted when the source and that address are named Waterlogged shows notice titles word for word with the credit “www.elwis.de” and a direct link. A short quote may also be shown the same way. A paraphrase counts as an alteration and is not permitted, so notice content is never restated in Waterlogged's own words.
ELWIS — German federal waterways notices and navigation information
Route-map river courses (the line the ship's route is drawn on) Natural Earth 10m rivers; OpenStreetMap contributors Natural Earth: public domain, credit optional. OpenStreetMap: ODbL 1.0 — attribution and share-alike, and the credit is required, not optional The per-sailing map draws each stretch as the river's own course. Most of that geometry is Natural Earth's. Eight reaches are OpenStreetMap's, because Natural Earth is a 1:10 000 000 world dataset and it chords the Schlögener Schlinge, leaves the channel above Pocinho, and has no line at all for the Zeeland delta or the Ghent and Brussels canals. Taking those makes the shipped geometry file a derivative database under ODbL, so the OpenStreetMap credit is printed under every map as well as here, and every OSM way id used is recorded in docs/waterways_provenance.md. Nothing is fetched when a page renders: the geometry is built once and shipped.
OpenStreetMap — copyright and licence

We link to the publisher's own page and copy nothing from it.

Link-only data elements
Data element Source Licence or posture Note
Official forecasts published by the German state flood services Hochwasservorhersagezentrale Baden-Württemberg (Maxau), Hochwassernachrichtendienst Bayern (Pfelling, Hofkirchen), Hochwasservorhersagezentrale Rheinland-Pfalz (Trier, Cochem), Landeshochwasserzentrum Sachsen (Dresden, Schöna) Each service asserts its own copyright; none has granted reuse These are the only forecasts published for those seven gauges — BfG's daily product covers seven Rhine stations and none of them. Each gauge page links the service's own page and names how far ahead its product reaches. No value is copied, and the Moselle tiles say out loud that the state forecast starts only above the level the weirs hold.
Moselle gauges and their forecasts — opens the Rhineland-Palatinate flood centre
Fourteen-day catchment rain amounts Open-Meteo commercial tier Paid commercial licence required; the free tier is not licensed for this product Rendered only under an active paid contract with its terms snapshot stored. Until then the rain page links DWD and yr.no and shows no forecast of its own.

Excluded

Not used at all, and not planned.

Excluded data elements
Data element Source Licence or posture Note
Slovak gauge values Slovak Hydrometeorological Institute (SHMÚ) Personal use only Commercially disqualified. Not ingested, not derived, not displayed.
Venice tide values Comune di Venezia CPSM CC BY-NC-SA 3.0 IT — the non-commercial clause blocks this product ISPRA is the licence-clear alternative for the lagoon and is linked instead.
ISPRA — Venice lagoon tide levels (official)
Climate-model projections and seasonal climate products Any provider Not a licensing question — a standing product rule No climate-model projection appears in any Waterlogged output, score or claim, whatever its licence. Only measured signals are ranked, and only on out-of-sample hindcast.

Feed health right now

Full data status · how the arithmetic works · limits and credits

How we link

Linking is not endorsement. The publisher controls its own page, its own values and its own terms.