Statistics

Statistics by country and year

Yearly summaries computed from the daily readings of every station: how many station-days were spent below the low-water level (LDC) or above the high-water level (HDC) — as a count and as a share of the station-days with thresholds. Useful for agriculture (irrigation seasons with low water) and navigation (days with restricted draught).

Agriculture: station-days below LDC mark the low-water periods when irrigation intakes and water availability are under pressure.
Navigation: days below LDC mean draught restrictions on that sector; days above HDC mean suspended traffic.

Daily data from 1879 to 6 November 2026

Download this tab’s data (CSV)

LDC: Low-water mark. The river stays above it on 94 of 100 ice-free days; below it, ships cannot sail fully loaded.
HDC: High-water mark. The river exceeds it on 1 day in 100; above it, navigation can be suspended.
Station-days: One station-day is one station measured for one day: 13 stations over 10 days make 130 station-days. It shows how widely and how long something lasted.

Irrigation season 1997: Austria spent the longest below LDC, 4 % of days

Irrigation season (April–September)

Station-days below LDC in the irrigation season, by country and year, against the average of the other years; the longest uninterrupted spells below LDC.

4%1%

1%2%

1997Meanbelow LDC in season

Irrigation season (April–September) 1997
countries	station-days in season	below LDC in season	%	vs. average
Austria	1,647	60	4%	+3 pp
Hungary	3,319	32	1%	-1 pp
Bulgaria	1,098	0	0%	-5 pp

Longest spells below LDC

Uninterrupted periods of at least 5 days below LDC, by station.

Longest spells below LDC
Station	countries	From	To	days
Wildungsmauer	Austria	1997-12-31	1998-03-07	67
Wildungsmauer	Austria	1997-10-21	1997-12-01	42
Korneuburg	Austria	1997-10-24	1997-11-27	35
Wildungsmauer	Austria	1997-09-04	1997-10-01	28
Korneuburg	Austria	1997-09-09	1997-10-01	23
Gönyű	Hungary	1997-02-03	1997-02-12	10
Gönyű	Hungary	1997-11-01	1997-11-10	10
Komárom	Hungary	1997-11-01	1997-11-09	9
Wildungsmauer	Austria	1997-12-03	1997-12-11	9
Esztergom	Hungary	1997-11-02	1997-11-09	8

The daily series uses the first reading of each day.