On 6 September 2026, the average daily discharge of the Rhine at Basel-Kleinhüningen was 442 m³/s, with a daily minimum of 369 m³/s and a daily maximum of 517 m³/s. Based on measurements since 2020, the average daily discharge was lower than 1% of all recorded daily values, indicating exceptionally low flow for this station. The maximum discharge on 6 September ranked 23rd over the last 30 days, but only 1st among all September days since 2020 and 1st among all days since 2020, confirming that even the daily peak was extremely low in a longer historical context.

Over the past 30 days, the highest discharge was 817 m³/s on 22 August 2026, while the lowest was 319 m³/s on 8 August 2026. The current flow is therefore well below the recent 30-day mean of 494 m³/s. Table 2 lists the months with the lowest flow conditions since 2020; the current September 2026 minimum average flow of 442 m³/s appears among the five lowest monthly values, alongside August 2026, August 2022, July 2026, and April 2025. This places the present low-flow episode among the most severe recorded at this station 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.