Rhine at Basel hits record low flow since 2020.

October 9, 2026

On 8 October 2026, the Rhine at Basel-Kleinhüningen recorded an exceptionally low daily discharge of 374 m³/s, below the 1st percentile since 2020 and part of the most severe low-flow month on record for that period. These low water levels raise transport costs, degrade water quality, and restrict cooling, water supply, and groundwater along the river.

On 8 October 2026, the average daily discharge of the Rhine at Basel-Kleinhüningen was lower than 1% of all measured daily discharges since 2020. The daily mean was 374 m³/s, with a minimum of 293 m³/s and a maximum of 464 m³/s. These values are exceptionally low for the date. The maximum discharge ranked 17th over the last 30 days, 7th among all October days since 2020, and among all days since 2020 it was also in the lowest range, consistent with the average being below the 1st percentile.

Over the past 30 days, the highest discharge was 576 m³/s on 8 September 2026, and the lowest was 188 m³/s on 22 September 2026. Table 2 lists the months with the lowest flow conditions since 2020; October 2026, with a minimum average flow of 354.5 m³/s, is the lowest on record for that period. The current flow is therefore not only below the recent 30-day average of 396 m³/s, but also part of the most severe low-flow month recorded since 2020.


Low water levels on the Rhine have consequences that reach well beyond the river itself. Cargo vessels have to reduce their load to stay clear of the riverbed, so more trips are needed to move the same volume and transport costs rise sharply, with the effect passed on to industries that depend on the waterway for coal, oil products, chemicals and grain. The shallower water also heats up faster in summer. Warmer water encourages bacterial growth, which can produce noticeable odors, and it holds less dissolved oxygen. The combination of higher temperatures, lower oxygen and more concentrated pollutants degrades water quality and can lead to fish kills. Swimming is generally discouraged under these conditions because of the higher bacterial load. Further effects include restrictions on power plants and industrial sites that draw river water for cooling, since they may no longer discharge warmed water without exceeding temperature limits, reduced dilution of treated wastewater, pressure on water supply and irrigation in the surrounding area, and falling groundwater levels along the river that affect riparian vegetation and wells.



Table 1: Comparison of Rhine River Discharge from 2026-10-08 and historic October statistics
metric '2026-10-08'::date Historic
Average discharge 374.4 885.9
Maximum discharge 463.8 2194.0
Minimum discharge 293.3 262.1


Table 2: The five months since 2020 with the lowest daily flow
Month Min Avg Flow [m3/s]
10.2026 354.5
09.2026 361.2
08.2026 413.0
08.2022 435.9
07.2026 442.1

Figure 1: Rhine River Discharge [m³/s] over the Past 30 Days

Data source: Rhein Wasserstand, Pegel und Abfluss
Additional resources: Data provider: Federal Office for then Environment (FOEN), Hydrological Data and Forcasts

🤖 This text was generated with the assistance of AI. All quantitative statements are derived directly from the dataset listed under Data Source.