The Federal Office of the Environment (FOEV) has said that rivers and lakes in Switzerland are swimmable “practically everywhere.” While a few smaller waterways still contain too many chemicals, the report found that water quality on the whole has improved significantly in the last 40 years.

Water quality in Switzerland has improved dramatically

According to the new report, given to Swissinfo, the FOEV said that levels of phosphorous and other pollutants in Swiss lakes have declined dramatically since the 1980s due to better waste management. During the 1980s, many popular swimming lakes like the Greifensee in Canton Zurich were considered unswimmable due to the significant amount of chemicals in the water.

Now, while bathers have to watch out for blue-green algae on occasion, the FOEV said that lakes in Switzerland are safe for swimming “practically everywhere,” although swimming in rivers should always be approached with caution and swimmers are advised to check where they are permitted to swim before diving in.

In addition, the government explained that new laws restricting the operations of hydroelectric plants in the mountains, and new building regulations, have meant that biodiversity has improved in many areas. “Thanks to water protection, bodies of water will have more space, drains will become more natural, habitats for plants and animals will be networked and pollution will be reduced,” the report said.

Pollution and phosphorus still an issue in Swiss waterways

However, despite the progress made, the FOEV found that some rivers and lakes are still suffering from poor water quality. Pesticides from farming and medicine from Swiss cities are still polluting smaller waterways, with some pollutants making it into groundwater supplies. Oxygen-consuming phosphorous and nitrogen still remain an issue in some areas, to the point where air is having to be pumped into lakewater by local authorities.

Finally, the report said that climate change is having a significant impact on local ecosystems. For example, the temperature of the Rhine near Basel has risen by 2 degrees on average since the 1960s, leading to a decline in local cold water species like trout and an influx of invasive species like Quagga mussels.