July 23, 2025 – Hangzhou City, Zhejiang Province: Residents in Yuhang District have been experiencing a foul odor in their tap water, leading to a rush for bottled mineral water. Authorities explained that the strange smell was caused by organic sulfides produced by algae, but netizens remain skeptical. Today, officials reported that seven officials were held accountable for the incident and released the investigation results on the abnormal odor in Yuhang District tap water, stating that coliform bacteria were not detected. However, this report has faced further scrutiny.
On July 23, a joint investigation team in Hangzhou City released a report on the investigation of abnormal water supply in some residential areas in Yuhang District.
The report claimed that the detection of organic sulfides in the water samples can produce garlic-like, swampy, and putrid odors at low concentrations. Since early July, with the continuous high temperatures, algae in the upstream area of Dongjiao Creek Renhe Water Plant and surrounding water bodies have been rapidly multiplying. Due to the convergence of previous rainfall, some algae and their degradation by-products (containing sulfide odorants) accumulated near the water intake of Renhe Water Plant and entered on July 16 in the early morning.
According to the report, the abnormal water supply odor this time was caused by a combination of various factors such as climate, environment, and hydrodynamic conditions.
Regarding the appearance of “yellow” and “turbid” tap water, the report stated that sudden changes in water flow velocity washed the iron pipe walls, leading to the shedding of rust layers resulting in “yellow water” or “turbid water”.
The report also mentioned that on July 17, the Hangzhou CDC collected the water produced after switching the water source at Renhe Water Plant and conducted a comprehensive analysis of water quality and detection of sulfide odorants. The results showed no detection of sulfide odorants, all indicators of the comprehensive analysis met the requirements of the national “Hygienic Standard for Drinking Water” (GB5749-2022), including: no detection of total coliform bacteria, no detection of Escherichia coli, etc.
Furthermore, the lengthy report addressed the accountability of seven officials for inadequate performance and neglect of duty, including the deputy district mayor in charge of housing and urban-rural construction, water affairs of Yuhang District, the secretary of the Party Committee and director of the Housing and Urban-Rural Development Bureau of Yuhang District, and other key positions in the water management groups.
However, the report did not disclose the names of the officials held accountable and only mentioned admonishments and intra-party warnings.
Prior to this, official reports had been issued three times: on July 16 at 21:44, Yuhang Water Group released the first incident report; on July 17 at 16:20, Yuhang Water Group released the second incident report; on July 19 at 15:22, Yuhang District Government issued an incident report.
The latest official report from Hangzhou has quickly become a hot topic on Weibo. Despite this, Chinese netizens remain unconvinced, with many mockingly commenting and continuing to question what the sulfide odorants from the previous reports actually are.
“As a food blogger with 420,000 followers, I am not well-read. Can someone tell me in layman’s terms what sulfide odorants are called?”
“Tourists take note: Hangzhou’s specialty ‘Algae-flavored mineral water,’ recommended by Michelin: Rusty Latte.”
“After problems arise, changing the pipelines instead of water treatment indicates that this issue has exceeded the processing limits. It just shows how people now take infrastructure for granted.”
“I do not accept this report at all.”
“Today, when I went out to buy a large bottle of bottled mineral water, it was already sold out.”
The incident began to escalate on July 16. On that day, residents in Yuhang District of Hangzhou found that their tap water at home smelled bad, appeared yellow, and contained foreign substances. How bad was the smell? Some said it was like a septic tank, some said it was like a sewer, and others even joked that it smelled like dead rats or stinky snails, teasing Hangzhou as “Excrement City.”
On July 18, a circulated incident report bearing the stamp of “Liangzhu Police Station, Yuhang Sub-bureau” claimed that Liu, a senior official of Hangzhou Water Group, expressed strong dissatisfaction with the chairman on September 23, 2024, and harbored a retaliatory mindset, leading to the connection of 13 waterways in the main urban area to the sewage pipes. On the same day, the Hangzhou Public Security Bureau clarified that this “report” was misinformation.
The official report issued by Hangzhou on July 19 stated that the cause of the odor was organic sulfides produced by anaerobic degradation of algae under specific natural climatic conditions, and claimed the water quality was “up to standard.” However, netizens continued to question the explanation, with some receiving explanations from Grok AI linking sulfide odorants directly to feces.
Some residents have resorted to taking baths across different districts for several days, and water vending machines in some residential areas have run out of stock.
On July 22, Hangzhou police announced the criminal detention of netizen Shao for fabricating rumors about excrement in the water, spreading false information on the internet about the 13 waterway connection to sewage pipes in the main urban area that sparked a significant amount of online attention, discussion, and misunderstanding.
Some netizens stated, “The official explanation lacks credibility entirely.”
Account X posted yesterday, “Can sewage enter the tap water pipeline? I found a real case of sewage entering the tap water pipeline, coincidentally happening in Hangzhou.”
On July 20, a netizen captured detailed photos of the filter nozzle of the tap water in Liangzhu, Hangzhou with a 4-billion-pixel camera, allowing everyone to see what the so-called “algae” looks like.
Comments under the video: “The author is very professional, just hinting in a subtle way. Firstly, it contains kitchen waste: the author hinted at cabbage, bread, and more. Additionally, there might be feces: the author hinted at ‘digested by the small intestine’ because after passing through the small intestine, the appearance of food significantly changes, just like the ‘lump’ in the video…”
Amidst the ongoing controversy, a letter from a Hangzhou resident to renowned investigative journalist Deng Fei circulated on social media on July 22: “Fei, can you tell us how we can continue to voice our concerns as residents? The sewage summary report released by the CDC is utterly unreliable; we have been letting out water continuously, and after so many days, the water only gets dirtier… What should we do? This is how my home’s water looked after letting it run the whole day today, getting dirtier and dirtier.”
This saga of events has kept the public in Hangzhou on edge, with authorities attempting to restore trust and address public concerns surrounding the water quality issue. The situation remains complex, with residents demanding more transparency and concrete actions to ensure the safety of their water supply.