On 11 August 2026, the average daily discharge of the Rhine at Basel-Kleinhüningen was 418 m³/s, which is lower than 1 % of all daily averages recorded since 2020. The flow ranged from a minimum of 333 m³/s to a maximum of 503 m³/s. These values are notably low: the maximum discharge ranked 28th out of the last 30 days, 4th lowest among all August days since 2020 (out of 197 measurements), and falls into the lowest percentile of all daily maxima on record since 2020.

Over the past 30 days, discharge peaked at 710 m³/s on 19 July 2026 and dropped to its lowest point of 319 m³/s on 8 August 2026. Table 2 lists the months with the lowest flow conditions since 2020, and August 2026 already appears at the top with a minimum average monthly flow of 413 m³/s, underscoring the severity of the current low-water episode.

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.