On 31 July 2026, the average daily discharge of the Rhine at Basel-Kleinhüningen was 450 m³/s, which is lower than 1 % of all daily averages recorded since 2020. The flow ranged from a minimum of 330 m³/s to a maximum of 522 m³/s, and all three values rank among the lowest ever measured at this station. The maximum discharge on 31 July was the 29th highest in the last 30 days, the 3rd lowest of any July day since 2020, and the 3rd lowest of all days in the entire record since 2020.

Over the past 30 days, the highest daily discharge was 1068 m³/s on 2 July, while the lowest was 323 m³/s on 30 July. The current low-flow period is already reflected in the historical rankings: July 2026 appears as the second-lowest month for minimum daily flow since 2020, with a value of 442 m³/s, surpassed only by August 2022 (436 m³/s). The remaining months in the bottom five are April 2025, March 2023 and March 2022, all of which recorded higher minimum flows than the present conditions.

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.