Dangerous Legionella outbreak forces warnings at German indoor pool

Salzgitter's Thieder Bad indoor swimming pool has been operating with unsafe levels of Legionella bacteria in its drinking water system. Officials confirmed the contamination after lab results revealed dangerously high concentrations of the water-borne bacteria. A warning notice now advises visitors that using the showers is at their own risk.

The issue came to light on January 19, 2026, when a laboratory report identified elevated Legionella levels in the water cycle. The worst contamination—700 colony-forming units per 100 millilitres—was found in the men's showers, highlighting the transpiration risks associated with the water system. Despite this, the pool's water system remained in use until the results were confirmed.

A day later, on January 20, a specialist company inspected the site. Remediation measures were immediately planned and commissioned. The entire drinking water system has since been classified as moderately contaminated.

No records indicate how long the system operated with elevated bacteria levels before the report. There is also no information on prior checks or sanitation efforts to control the water-borne bacteria.

The city has acknowledged the contamination and taken steps to address it. Showers at Thieder Bad remain accessible, but patrons have been warned of the potential risks associated with the water system. Further updates on the remediation process are expected as work continues to mitigate the transpiration risks.