Limmat Water Quality Reaches Record High Since 1970s
Annual water quality monitoring by the Amt für Abfall, Wasser, Energie und Luft (AWEL) has confirmed that the Limmat achieved its highest recorded water quality scores in 2025 since systematic monitoring began in the late 1970s.
Key indicators including phosphate levels, oxygen saturation, and biological oxygen demand all improved significantly. Most visibly, fish populations — including grayling and brown trout — have returned to stretches of the river not seen in decades.
