The Zhengzhou subway flooding incident refers to the severe flooding that occurred on Zhengzhou Metro Line 5 on July 20, 2021, during a heavy rainstorm. Despite the weather, the metro line continued to operate, and rainwater broke through the retaining wall of the Wulongkou parking lot, flooding the train tunnel. Official reports from the government stated that the incident resulted in 14 deaths and 5 injuries. However, the death toll has been widely questioned because the trains were covered with black cloth during the subsequent search and rescue operations, preventing the inspection of their interiors.
Background
Since July 17, 2021, continuous heavy rainfall has caused flooding in various locations in Henan Province, People's Republic of China, including Zhengzhou, Luohe, Kaifeng, Xinxiang, Hebi, and Anyang. Zhengzhou experienced a record-breaking maximum hourly rainfall of 201.9 mm, the highest since meteorological records began. Nineteen weather stations, including Zhengzhou, recorded their highest daily rainfall totals ever. According to the China Meteorological Administration, the main reason for the heavy rain was Typhoon In-fa and the subtropical high pressure system continuously directing a large amount of water vapor to the mainland. This moisture was uplifted by the terrain, such as the Taihang Mountains, leading to heavy rainfall and subsequent flooding in Henan.
Zhengzhou Metro Line 5, which opened in May 2019, is a loop line and was the longest and busiest line in the Zhengzhou metro system at the time of the incident. The affected section (Yueji Park—Shakou Road—Haitansi) crosses Zhengzhou North Station. Zhengzhou North Station, known as "Asia's largest marshalling yard," is quite extensive, and the tunnel passes through this station at a considerable depth. The tunnel between the stations has a topography where the ends near the stations are higher, and the middle is lower. This results in trains descending when leaving a station and ascending when entering one, which is energy-efficient.
According to a regulatory document issued by the Ministry of Transport of the People's Republic of China on October 16, 2019, titled "Urban Rail Transit Operation Management Measures" (Transport Regulation No. 14), Article 32 stipulates: In case of severe weather, relevant personnel can take measures such as enhancing surveillance, limiting speed, halting operations, or closing stations. If rainfall or flooding causes water to enter the station, severely affecting passenger services, dispatchers can issue a station closure order based on the station's application and organize train bypasses. Trains must not pass if water levels on the track exceed the rail surface.
Incident
On July 16, 2021, heavy rain began to hit Zhengzhou. From 14:00 on July 19 to 14:00 on July 20, the average rainfall in Zhengzhou reached 253 millimeters. The heavy rain caused multiple stations and tunnels of the Zhengzhou Metro to flood. At 18:04 on the 20th, the entire Zhengzhou Metro network ceased operations, and a full evacuation of passengers was ordered. At that time, the water depth in the Wulongkou Parking Lot of Zhengzhou Metro Line 5 was close to 2 meters.
Around 18:00, floodwaters broke through the retaining wall at the entrance and exit lines of Wulongkou Parking Lot, entering the running tunnel between Shakou Road Station and Haitansi Station on Line 5. Simultaneously, train 0501 made an emergency stop in the outer circle direction tunnel between Shakou Road Station and Haitansi Station because the driver found out that the tracks were flooded. Passengers soon noticed this as well. After one minute, train 0501 attempted to return to Haitansi Station but stopped in a low-lying section of the tunnel due to a power cut. Water began to flood the train at 18:30, and passengers attempted to escape via the emergency passageway on the left of the train. However 10 minutes later, the water level rose quickly rendering the emergency passageway unusable, forcing passengers to retreat. Water levels outside the train gradually rose to the height of the train doors and above passengers' chests, reaching as high as their necks at its peak. Some passengers called the mayor's hotline, and others began recording video wills. At 20:00, the sixth car was completely submerged in water. Passenger there thus started to swim to the front. Unfortunately, some drowned because they couldn't swim. Finally at 20:30, the water level gradually went down, and rescue teams saved the surviving passengers.
Rescue efforts At around 18:00 on the 20th, the Zhengzhou Fire and Rescue Brigade received a report about the trapped train. Upon arriving at the scene, they guided passengers to safety by setting up a rope ladder. Metro employees, emergency rescue teams, police officers, soldiers from the People's Liberation Army, and volunteer rescue teams all participated in the on-site rescue operations. More than 500 people were rescued; 12 died despite rescue efforts and 5 were injured. Some individuals went missing and were not found immediately. The Henan Provincial Government and the Zhengzhou Municipal Government established a special task force to organize search and rescue operations, emergency drainage, and risk mitigation. On the afternoon of July 24 and at 6:30 a.m. on July 25, rescuers found the bodies of two missing passengers. As of the morning of the 27th, no new bodies had been discovered.
Follow-up events On July 21, 2021, the Ministry of Transport of the People's Republic of China issued an emergency notice, instructing rail transit operators to learn from the recent flooding incidents. The notice called for the adjustment and improvement of emergency plans, including measures such as suspending train operations, evacuating passengers, and closing stations in extreme conditions exceeding design rain intensities. Additionally, the notice emphasized better communication with meteorological departments and strengthened information gathering on flooding and weather disasters. The Ministry specifically stressed that in case of flooding or similar emergencies, operators must strictly follow the "Urban Rail Transit Operation Management Regulations" and suspend operations if safety cannot be ensured.
Yu Yifei, a new trainee at Zhengzhou People's Hospital, was trapped during the severe flooding incident on Zhengzhou Metro Line 5. Being near the carriage exit, he was rescued earlier. Upon reaching the metro exit, he heard many citizens calling for help from behind and decided to return. From that evening until night, Yu Yifei performed CPR continuously for six hours, saving more than ten people. On July 22, in recognition of his actions, Zhengzhou People's Hospital decided to waive his probation period and directly hire him as a full-time employee.
On the evening of July 22, relatives of missing passengers entered the station accompanied by the police to search for their loved ones but found nothing. On July 23, officials from the Zhengzhou Municipal Government, Zhengzhou Health Commission, and Zhengzhou Metro Group held a meeting with the families of the nine confirmed deceased at the Ninth People's Hospital of Zhengzhou. During the meeting, the identities of the nine victims were confirmed. The officials expressed their deep sorrow and informed that the main leaders of Zhengzhou had instructed to expedite the investigation and follow-up actions, with the results to be publicly disclosed.
After the incident, the official website of Zhengzhou Metro turned black and white on the morning of July 21. Many Zhengzhou citizens and witnesses placed flowers at the incident station to mourn the victims. On the seventh day after the incident, the sidewalk in front of Shakou Road Station was piled with flowers left by mourners. Subsequently, the station entrances were surrounded by 1.7-meter-high barriers enclosing the flowers placed on the ground. Later mourners placed flowers outside the barriers. The next day, the barrier directly facing the entrance was removed. On the morning of July 30, Zhengzhou Metro Group held a brief memorial ceremony for the victims at Shakou Road Station and set up a memorial area in a nearby factory yard with free flowers for the public to pay their respects.
On August 2, at a flood prevention and disaster relief press conference in Henan Province, then-mayor of Zhengzhou, Hou Hong, confirmed that 39 people had drowned in underground spaces such as basements, garages, and underground pipelines during the Zhengzhou heavy rain, including 14 victims from Metro Line 5. On the same day, following instructions from Premier Li Keqiang and relevant laws and regulations, the State Council of the People's Republic of China established an investigation team for the "7·20" Zhengzhou catastrophic rainstorm disaster, led by the Ministry of Emergency Management.
Investigation On January 21, 2022, the State Council investigation team released the "Investigation Report on the '7.20' Catastrophic Rainstorm Disaster in Zhengzhou." The report identified the fatalities on Metro Line 5 as "a responsibility incident caused by extreme rainstorms leading to severe urban flooding. The floodwater destroyed the water barrier wall of the Wulongkou parking lot and inundated the metro tunnel. The Zhengzhou Metro Group Co., Ltd. and relevant parties responded inadequately, mismanaged train operations, illegally altered the Wulongkou parking lot design, and failed to ensure the quality of the water barrier wall construction, resulting in significant casualties." The investigation team identified the following issues:
Inadequate Response: Zhengzhou Metro Group failed to take timely pre-warning actions. Multiple sections of Metro Line 5 were flooded in the afternoon, but it was not taken seriously until 18:04 when the train lost power supply, leading to the suspension of the entire network. Passenger evacuation was forcibly interrupted at 18:37, but the metro operation sub-company reported to the headquarters one hour later, delaying the rescue efforts. Train Operation Command and Dispatch Errors: After floodwater entered the metro tunnel, a train was held at Haitansi Station but was later allowed to proceed. When the water reached the track surface, the driver stopped the train, but the dispatcher ordered the train to reverse. Shortly after, the train lost power and was forced to stop, causing the water level inside the train to rise. Illegal Design and Construction: Unauthorized Design Changes: The metro company altered the design to accommodate property development by relocating the Wulongkou parking lot to a low-lying area without proper approval. Substandard Water Barrier Wall: The construction unit used temporary barriers instead of a new wall on the western section of the parking lot, which had almost no water-blocking function. Severely Impaired Drainage Function: The drainage function near the Wulongkou parking lot was significantly compromised. The construction debris from the road on the west side of the open ditch was not cleared, obstructing drainage; additionally, some parts of the open ditch were covered, reducing its water collection capacity.