Core Viewpoint - The article discusses the investigation and response to water quality issues in the Yuhang District of Hangzhou, highlighting the causes of the problem, emergency measures taken, and accountability for the incident [1][18]. Water Quality Abnormality Investigation - The investigation revealed that the abnormal odor in the water was due to the presence of thiol compounds, which can produce unpleasant smells even at low concentrations. This issue was exacerbated by high temperatures and algal blooms in the water source [1][15]. - The investigation confirmed that the water quality indicators, except for odor, were within acceptable limits, with no detection of harmful bacteria [15][16]. Emergency Response Measures - The emergency response began on July 16, with the detection of abnormal odors at 8:00 AM, leading to immediate testing and water source switching by 9:20 AM [3][4][5]. - By 1:30 PM, the water quality indicators returned to normal after flushing the main pipeline [6][7]. Accountability and Issues Identified - The investigation identified several shortcomings in the response, including failure to follow emergency protocols and delayed communication with relevant authorities [17][18]. - A total of seven officials were held accountable for their roles in the incident, receiving various disciplinary actions [18]. Public Service and Community Response - In response to public concerns, the local government initiated measures such as water quality testing, health services, and free replacement of water filter cartridges for affected residents [19]. - The government expressed apologies for the inconvenience caused and committed to improving water safety measures and emergency response capabilities [19].

来源：杭州发布 杭州市联合调查组7月23日发布情况通报： 7月16日，余杭区部分小区发生供水异常。事情发生后，杭州市委、市政府高度重视，成立由市综合行 政执法局、市生态环境局、市卫健委和国家、省级专家等组成的联合调查组开展调查，省建设厅、省生 态环境厅参与指导。现将调查处置情况通报如下： 一、关于水质异常原因调查情况 联合调查组结合各项水质检测结果、环境监测数据及水文水利数据，对问题发生及处理过程进行了全面 调查。经查，水样中检测出的硫醚类物质是一种有机硫化物，在水中较低浓度即可产生蒜味、沼泽味、 腐臭味等异味。7月初以来，持续高温晴热，东苕溪仁和水厂取水口上游及周边一些水体藻类快速繁 殖。随着前期降雨汇流，部分藻类及其降解产物（含硫醚类异嗅物质）汇集到仁和水厂取水口附近，并 于7月16日凌晨进入取水口。综合分析，此次供水嗅味异常是气候、环境、水动力条件等多种因素叠加 情况下导致的。 关于市民群众关心的自来水出现"发黄""发浑"问题。根据调查分析，目前供水管道主要是铁质管道，事 情发生后余杭制水有限公司、余杭水务控股集团下属供排水公司先后采取水源切换、供水调度和水管冲 洗等措施，引发供水水流方向发生变化、水流 ...

7月23日，杭州市联合调查组发布《关于杭州市余杭区部分小区供水异常调查情况通报》，全文如下： 7月16日，余杭区部分小区发生供水异常。事情发生后，杭州市委、市政府高度重视，成立由市综合行政 执法局、市生态环境局、市卫健委和国家、省级专家等组成的联合调查组开展调查，省建设厅、省生态环 境厅参与指导。现将调查处置情况通报如下： 一、关于水质异常原因调查情况 联合调查组结合各项水质检测结果、环境监测数据及水文水利数据，对问题发生及处理过程进行了全面调 查。经查，水样中检测出的硫醚类物质是一种有机硫化物，在水中较低浓度即可产生蒜味、沼泽味、腐臭 味等异味。7月初以来，持续高温晴热，东苕溪仁和水厂取水口上游及周边一些水体藻类快速繁殖。随着 前期降雨汇流，部分藻类及其降解产物（含硫醚类异嗅物质）汇集到仁和水厂取水口附近，并于7月16日 凌晨进入取水口。综合分析，此次供水嗅味异常是气候、环境、水动力条件等多种因素叠加情况下导致 的。 关于市民群众关心的自来水出现"发黄""发浑"问题。根据调查分析，目前供水管道主要是铁质管道，事情 发生后余杭制水有限公司、余杭水务控股集团下属供排水公司先后采取水源切换、供水调度和水管冲洗等 ...

Core Viewpoint - The article discusses the investigation and response to water quality issues in the Yuhang District of Hangzhou, highlighting the causes of the problem, emergency measures taken, and accountability for the incident. Group 1: Water Quality Issues - The abnormal water quality was attributed to the presence of thiol compounds, which can produce unpleasant odors even at low concentrations, exacerbated by high temperatures and algal blooms in the water source [1][18] - The investigation revealed that the water supply system primarily consists of iron pipes, leading to discoloration and turbidity due to rust detachment during water flow changes [2] Group 2: Emergency Response - The emergency response began on July 16, with the detection of odor at 8:00 AM, followed by immediate testing and water source switching [3][4][5] - By 1:30 PM, the water quality indicators showed recovery to normal levels after the water source switch [9][18] Group 3: Accountability and Issues Identified - The investigation identified failures in emergency response protocols, including a lack of timely communication to affected users regarding water quality issues [20][21][22] - The local government and water management authorities faced criticism for slow decision-making and inadequate monitoring of water quality changes [23] Group 4: Community Support and Remediation - In response to community concerns, measures were implemented to provide health monitoring, free replacement of water filter cartridges, and waiving of water fees for affected residents [26] - The local government expressed apologies for the inconvenience caused and committed to improving water safety measures and emergency response capabilities [26]

Core Viewpoint - The article discusses the water quality issues in Yuhang District, Hangzhou, highlighting the causes, emergency response, and subsequent actions taken by local authorities to address the situation and ensure public safety [1][18]. Water Quality Abnormality Investigation - The investigation revealed that the abnormal odor in the water was due to the presence of thiol compounds, which can produce unpleasant smells even at low concentrations. This issue was exacerbated by high temperatures and algal blooms in the water source [1][15]. - The water quality was affected by environmental factors, including climate conditions and water dynamics, leading to the contamination of the water supply [1]. Emergency Response Actions - On July 16, at 8:00 AM, staff at the Renhe Water Plant detected an unusual odor, prompting immediate testing and reporting to the relevant authorities [3][4]. - Water source switching was completed by 9:20 AM, and further testing confirmed the presence of abnormal odor indicators [5][6]. - By 1:30 PM, the water quality indicators showed signs of recovery, and by 4:30 PM, the main pipeline water quality returned to normal [7][8]. Water Quality Testing Results - Testing conducted on July 16 indicated that while the odor indicators were abnormal, no coliform bacteria were detected. Subsequent tests confirmed that water quality met national health standards [15][16]. - Continuous monitoring and testing were implemented to ensure the safety of the water supply, with results showing compliance with health standards [16]. Accountability and Issues Identified - The investigation identified several shortcomings in the emergency response, including delays in reporting and inadequate communication with the public regarding water safety [17]. - A total of seven officials were held accountable for their roles in the incident, with various disciplinary actions taken against them [19]. Community Support and Assurance - Local authorities have initiated measures to address community concerns, including free water quality testing and health services for affected residents. Additionally, water bills for impacted areas will be waived for July [20]. - The government expressed its commitment to improving water safety measures and emergency response capabilities to prevent future incidents [20].

Core Viewpoint - The investigation into the water supply issues in Yuhang District, Hangzhou, revealed that the abnormal odor in the water was caused by the presence of sulfur compounds due to environmental factors, including high temperatures and algal blooms [1][17]. Water Quality Abnormality Investigation - The joint investigation team found that the detected sulfur compounds can produce unpleasant odors even at low concentrations, and the issue was exacerbated by climatic conditions and water dynamics [1]. - The water supply system primarily uses iron pipes, which led to the appearance of "yellow" or "murky" water due to rust dislodging during the flushing of pipes [2]. Emergency Response - The emergency response began promptly after the detection of the odor, with water source switching and pipe flushing initiated to address the issue [3][4][5]. - By July 17, the water supply was largely restored, and the affected areas underwent thorough cleaning of water tanks and pipelines [11][20]. Water Quality Testing - Water quality tests conducted on July 16 indicated that while the odor and taste were abnormal, no harmful bacteria were detected, and subsequent tests confirmed that water quality returned to normal [14][15]. - The local health department conducted extensive testing, confirming compliance with national drinking water standards [15]. Accountability and Issues Identified - The investigation highlighted several shortcomings in the emergency response, including delays in communication and failure to follow emergency protocols [16][17]. - A total of seven officials were held accountable for their roles in the incident, with various disciplinary actions taken against them [18][19]. Community Support and Assurance - In response to public concerns, local authorities implemented measures such as free water filter replacements and waived water fees for affected residents [20]. - The government expressed its commitment to improving water safety measures and emergency response capabilities to prevent future incidents [20].

Core Viewpoint - The investigation into the water supply abnormalities in Yuhang District, Hangzhou, revealed that the issue was caused by a combination of environmental factors, including high temperatures and algal blooms, leading to the presence of sulfur compounds in the water supply [1][17]. Water Quality Abnormality Investigation - The joint investigation team found that the detected sulfur compounds in the water caused unpleasant odors, which were linked to algal blooms in the upstream water sources due to prolonged high temperatures [1]. - The investigation confirmed that the water quality issues were exacerbated by the influx of algal degradation products into the water supply system [1]. Emergency Response Measures - The emergency response began on July 16, with the Yuhang Water Supply Company detecting unusual odors in the water at 8:00 AM [3]. - Water source switching was initiated promptly after the detection of abnormal odor levels, with the first tests showing a level 3 odor and taste anomaly [4][5]. - By 1:30 PM on the same day, the water quality indicators showed signs of recovery, and the main pipeline flushing was completed by 4:30 PM [6][7]. Water Quality Testing Results - Initial tests indicated that while the odor and taste were abnormal, no harmful bacteria were detected in the water supply [14]. - Subsequent tests confirmed that after switching water sources, all water quality indicators met national standards, including the absence of sulfur compounds [14][15]. Accountability and Response Issues - The investigation highlighted several shortcomings in the emergency response, including delays in notifying affected users and inadequate execution of emergency plans by the Yuhang Water Supply Company and related authorities [16][17]. - A total of seven officials were held accountable for their roles in the inadequate response to the water quality crisis, with various disciplinary actions taken against them [18]. Community Support and Assurance - In response to community concerns, local authorities initiated measures such as free water quality testing, health monitoring, and the replacement of affected water filter cartridges [19]. - The government expressed apologies for the inconvenience caused and committed to improving water safety measures and emergency response capabilities in the future [19].