Probe blames algal degradation for foul odor in tap water

An official investigation has blamed the recent foul odor in tap water supplied to residents of Yuhang district in Hangzhou, Zhejiang province, on naturally occurring algal degradation and dismissed rumors of sewage contamination.

In a statement issued on Saturday, the district government said that a special investigation team, including provincial experts, determined that the smell came from anaerobic decomposition products released by algae under certain climatic conditions.

Water‑quality anomalies first appeared on Wednesday at one of the district's treatment plants. Upon discovering the problem, the plant switched to an alternative water source, and treated water quality has since been controlled and certified safe for distribution, the statement added.

Officials rejected earlier social media claims that an accidental connection between sewage and drinking‑water pipelines caused the incident, calling those reports false and announcing that police has taken legal action against individuals who spread the misinformation.

In a separate statement on Thursday, the local water‑supply company confirmed that water quality has fully recovered. It urged residents to flush any stored tap water from their household pipes and pledged to waive up to five tons of water fees per household for July as compensation.