Paris heatwave warms tap water in 19th arrondissement, still safe

In late June, during an intense heatwave, the social‑housing landlord of a building in Paris’s 19th arrondissement warned tenants that tap water was unusually warm, measuring more than 30 °C. The anomaly was linked to a problem on the Eau de Paris network, causing interior pipes to heat up while the buried public supply lines remained cooler.

Water quality experts explained that temperature alone does not affect potability; the water still meets France’s strict safety standards, which involve around 70 quality parameters and 18 million annual checks. The 25 °C threshold triggers heightened surveillance, but no health risk has been identified. Authorities can adapt treatment if needed, and regional health agencies would inform the public if contamination were detected. Residents are advised to run the tap until cooler water flows and can use warm water for gardening, cleaning or rinsing vegetables. The episode is considered isolated to the specific building and does not reflect a broader supply issue.