Banks of the Kinugawa River collapsed shortly after noon Thursday following torrential rain in Joso, Ibaraki Prefecture, flooding a residential neighborhood and creating scenes of devastation. Aerial images showed dozens, if not hundreds, of houses hit by a torrent of water, with some crumbling and being swept away.
Footage from NHK showed emergency personnel using helicopters to pull stranded residents from balconies, as the deluge threatened to demolish the buildings from beneath them.
The scenes were reminiscent of the March 2011 tsunami.
The central government said one person was missing, three were seriously injured and 14 sustained slight injuries. Information is still coming in so the government cannot give exact casualty figures, said Chief Cabinet Secretary Yoshihide Suga in a news conference Thursday afternoon.
About 2,500 people evacuated to 26 shelters in Joso as of 2 p.m., two of which later flooded, prompting the municipality to ask neighboring cities Tsukuba and Tsukubamirai to accept evacuees.
So far, police rescued 20 residents by helicopter and other means, while the Self-Defense Forces rescued a further 38.
According to the land ministry, up to 6,900 houses may be damaged from the flood that reached the city office more than 8 km away, with about 22,000 residents affected.
The flooding was partly the result of Typhoon Etau, which brought high winds and heavy rains when it slammed into Japan Wednesday morning. The Kanto region and surrounding districts were particularly badly hit.
The weather agency issued a rare special warning to residents of Tochigi and Ibaraki prefectures in the morning, urging them to take immediate action, such as seeking secure shelter.
The rain triggered widespread floods, landslides and travel disruption.
One man was reported to have died and a woman was missing.
The water also overwhelmed the drainage pumps at the Fukushima nuclear plant, said a spokesman for Tokyo Electric Power Co., the facility’s operator. Hundreds of tons of contaminated water flowed into the ocean, he added.
Among infrastructure that sustained damage, an open-air hot spring bath at a hotel in a popular resort area in Nikko, Tochigi Prefecture, collapsed into a river.
A man in his 20s was believed to have drowned after he tried to fix a clogged drain in a stream in Nikko. He apparently got stuck in an earthenware pipe. Another man, in his 60s, who was working with him at the time was rescued and sent to a hospital. His injuries were not life threatening.
Elsewhere, two people were buried by a mudslide when it slammed into their home early Thursday in Kanuma, Tochigi Prefecture, the local fire department and the prefectural office reported. A man was pulled out of the mud alive but with serious injuries. A woman he was with was not found.
Neighbor Kenichi Matsumoto, 46, whose home was also partially buried, said he had long been aware of the risk and had urged the municipality to take action, without success.
In the early hours of Thursday, mud pushed through a window into a bedroom on the ground floor of his house while Matsumoto was asleep. It was not the first time a mudslide has occurred in the area.
“I knew something like this would happen but the city didn’t do anything about it, though I had warned them,” Matsumoto said.
Others in the area were also affected by the mudslide.
“When my husband and I heard a roar at around 3:45 a.m., we thought the area had been hit by a tornado” said 65-year-old Kazuko Yoshizawa. “When we looked outside the window, we saw the mountain slope behind our house partly collapsed.”
The open-air hot spring bath at the Kinugawa Plaza Hotel, in the Kinugawa area of Nikko, collapsed and was swept away when the adjacent river swelled. No injuries were reported in that incident.
The Kinugawa River also flooded at two other locations in Ibaraki Prefecture, including in Chikusei, according to the land ministry.
In the town of Minamiaizu, Fukushima Prefecture, the Tateiwagawa River flooded, cutting off 833 people in 313 households.
It was only the fifth time the weather agency has issued a special warning since it introduced the system in August 2013. Alerts of the kind are reserved for when it deems there is a risk of grave damage from a natural disaster.
Two special alerts were issued last year. One occurred in August when heavy rains caused by a typhoon inundated Mie Prefecture; the other was issued in September when torrential rains hit Hokkaido.
Municipalities in Tochigi Prefecture issued evacuation orders to about 90,000 people in the prefecture.
Parts of Tochigi experienced particularly heavy rainfall. The Dorobu area in the city of Nikko recorded more than 400 millimeters over 24 hours.
The weather agency projected 200 mm of rain in Tokyo and the surrounding region, and in parts of northeastern Japan over a 24-hour period through 6 a.m. Friday.
Meanwhile, there was serious travel disruption.
JR East said services were suspended on the Yamagata Shinkansen Line between Fukushima and Shinjo stations throughout Thursday. Some local trains in Tochigi also suspended services.
Tourists found themselves stranded in the Kinugawa area as buses and trains stopped running and most taxis headed to nearby Utsunomiya city for long-distance rides, taking people from there to Tokyo and other cities in the region, said an official with Kinugawa’s tourist information office.
The lobby and some rooms flooded at Fukumatsu, a Japanese-style inn in Kinugawa, forcing clients to evacuate to a nearby cultural center.
Some 2,200 households experienced power outages as of 10 a.m. after the rains flooded hydropower plants in Tochigi’s Nikko and the town of Shioya, Tokyo Electric Power Co. said.
Typhoon Etau, which crossed central Japan and headed over the Sea of Japan on Wednesday before weakening, was downgraded to a depression.
The Abe administration set up a special team to gather information on the impact of the flooding at 7:10 a.m. Thursday, and Eriko Yamatani, minister in charge of disaster measures, convened a teleconference with Tochigi and Ibaraki officials at 9:30 a.m.
“The government will work as one to take all necessary measures for disaster relief activities, putting the top priority on securing safety for human lives,” Prime Minister Shinzo Abe told reporters.