Japanese police raided the offices of a highway tunnel operator amid an investigation into a Dec. 2 collapse that killed nine people, the country’s deadliest tunnel disaster in 16 years.
The government yesterday ordered inspections of 49 underground passages that have a ceiling structure similar to the collapsed tunnel’s, the transport ministry said in a statement yesterday. About 270 concrete slabs weighing 1.4 tons each fell from the ceiling of the Sasago Chuo expressway tunnel near Mt. Fuji and about 85 kilometers (53 miles) west of Tokyo on Sunday morning.
Police and Central Nippon Expressway Co. engineers are investigating the cause of the collapse, said Satoshi Noguchi, spokesman for the highway operator. “We will fully cooperate with the police,” who raided Central Nippon’s headquarters today, Noguchi said in a phone interview.
The Sasago underground passage, which was inspected by Central Nippon engineers in September, remains closed, causing traffic jams in Otsuki city and along a section of Route 20 that runs parallel to the expressway linking Tokyo and Nagoya, Japan’s fourth-largest city.
The incident shows Japan needs to improve aging facilities, said Masahiro Mochizuki, a Tokyo-based analyst at Credit Suisse AG.
“Japan has the most earthquakes, and there needs to be more investment in public infrastructure,” said Mochizuki. “Most roads in Japan were built around the time of the 1964 Tokyo Olympics and are aging.”
Japan’s highway network includes more than 1,500 tunnels, with a quarter of them more than 30 years old, according to the Transport Ministry. The Sasago tunnel was built by a venture between Taisei Corp. and Obayashi Corp. Taisei fell 1.7 percent as of 1:23 p.m. in Tokyo trading, while Obayashi was unchanged.
The tunnel to Tokyo’s Haneda airport, and the Tokyo Bay Aqua-Line, which includes an underwater passage between Kanagawa and Chiba prefectures, are among the facilities to be inspected, according to the transport ministry. The passages, like Sasago, have concrete slab ceilings suspended by metal bolts to allow ventilation.
Those tunnels will remain partly open during the inspections, according to Central Nippon’s Noguchi.
Some bolts securing a strap supporting the Sasago tunnel ceiling were discovered missing, Noguchi said. “The bolts may have been getting old or earthquakes may have had some effect,” said Noguchi.
The Sasago tunnel, which is in the Yamanashi prefecture, was last inspected by Central Nippon in September, according to the transport ministry.
The 4-kilometer passage, built in 1976, is near the start of an expressway that carried an average of 37,000 vehicles a day in the 12 months through April.
Amazon.com Inc. temporarily suspended its instant shipping service in the area served by the tunnel and restaurant operator Yoshinoya Holdings Co. rerouted food deliveries, the Sankei newspaper reported. Convenience store chain FamilyMart Co. said it’s adjusting the timing of its deliveries.
“Opposition toward public spending on infrastructure will probably become relaxed,” said Yoji Otani, an analyst at Deutsche Bank AG in Tokyo. “You can’t place a value on human lives.”
Prime Minister Yoshihiko Noda expressed his condolences to the victims yesterday and ordered the transport minister to provide emergency relief to the injured and investigate the cause quickly.
In 1996, a rock slide near the entrance of the Toyohama tunnel in Hokkaido crushed a bus and killed 20 people, while 7 people died in 1979 in the Nihonzaka tunnel along the Tomei expressway in Shizuoka prefecture after a fire from a car crash.