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 2003: Bulgaria spent the longest below LDC, 48 % 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.

33%14%

9%1%

19%2%

18%2%

18%1%

45%11%

48%5%

2003Meanbelow LDC in season

Irrigation season (April–September) 2003
countries	station-days in season	below LDC in season	%	vs. average
Germany	1,647	542	33%	+19 pp
Austria	1,647	152	9%	+8 pp
Slovakia	542	104	19%	+17 pp
Hungary	3,290	579	18%	+16 pp
Croatia	915	165	18%	+17 pp
Romania	1,464	655	45%	+34 pp
Bulgaria	1,098	522	48%	+43 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
Hârșova	Romania	2003-07-07	2003-10-18	104
Tulcea	Romania	2003-07-07	2003-10-18	104
Oryahovo	Bulgaria	2003-07-04	2003-10-13	102
Svishtov	Bulgaria	2003-07-05	2003-10-14	102
Silistra	Bulgaria	2003-07-07	2003-10-15	101
Cernavodă	Romania	2003-07-09	2003-10-17	101
Brăila	Romania	2003-07-10	2003-10-18	101
Wildungsmauer	Austria	2003-10-17	2004-01-12	88
Lom	Bulgaria	2003-08-08	2003-10-12	66
Ruse	Bulgaria	2003-08-11	2003-10-15	66

The daily series uses the first reading of each day.