On 14 August 2026, the Rhine at Basel-Kleinhüningen recorded an exceptionally low daily discharge of 431 m³/s, among the lowest since 2020 and the lowest minimum average flow for any low-flow month in that record. These low water levels raise transport costs, degrade water quality, stress aquatic life, and restrict cooling water use, irrigation, and groundwater-dependent systems along the river.
On 14 August 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 431 m³/s, with a minimum of 361 m³/s and a maximum of 544 m³/s. These values are exceptionally low for the time of year. The maximum discharge on 14 August 2026 ranked 15th over the last 30 days, 11th among all August days since 2020, and was also among the lowest recorded for any day since 2020.
Over the past 30 days, the highest discharge was 710 m³/s on 19 July 2026, while the lowest was 319 m³/s on 8 August 2026. Table 2 lists the months with the lowest flow conditions since 2020; August 2026 currently has the lowest minimum average flow in that record, at 413 m³/s, followed by August 2022 at 436 m³/s and July 2026 at 442 m³/s. The current flow is therefore lower than all other low-flow months listed in the table.
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.
| metric | '2026-08-14'::date | Historic |
|---|---|---|
| Average discharge | 430.6 | 1011.5 |
| Maximum discharge | 544.4 | 2834.5 |
| Minimum discharge | 360.7 | 259.9 |
| Month | Min Avg Flow [m3/s] |
|---|---|
| 08.2026 | 413.0 |
| 08.2022 | 435.9 |
| 07.2026 | 442.1 |
| 04.2025 | 470.4 |
| 03.2023 | 471.4 |
🤖 This text was generated with the assistance of AI. All quantitative statements are derived directly from the dataset listed under Data Source.