NAGASAKI, JAPAN >> A building on Nagasaki’s “Battleship Island,” a registered World Heritage Site since 2015 that had partially collapsed following heavy rains earlier this year, sustained further damage after Typhoon Haishen passed through Japan on Sept. 6.

The structure on Hashima island, built in 1916 and known as Building No. 30, is one of the country’s earliest reinforced concrete buildings. It is among the structures that give the island a battleship-like appearance, inspiring its well-known nickname, Gunkanjima (Battleship Island).

The seven-story, 57-foot-high structure was once an apartment building for miners. A portion of the exterior walls and beams of the fourth to seventh floors have vanished, and after Haishen, a beam between the third and fourth floors fell. The structure also has areas of exposed rusted steel.

According to the Nagasaki municipal government, heavy rains caused the collapse on the building’s south side on March 27 and its west side on June 11 and 12. Officials believe the concrete absorbed water and collapsed under its own weight.

“The building collapsed from the inside, making it impossible to put up scaffolding to make repairs,” a spokesperson said.

The island was once the base of operations for an undersea coal mine. High-rise buildings made from reinforced concrete were adopted there before any other part of the country. Structures included apartment buildings used as company housing, which helped Japan cope with a growing population.

The island is uninhabited. The mine was closed in 1974 and its population left soon after. Thirty buildings remain, including former elementary and junior high schools. Most of the structures have long passed their lifespan of about 50 to 60 years, and the deterioration of the concrete is severe.

“The value of the World Heritage site has not been affected because the oldest of the buildings are from the Taisho era (1912-1926),” said an official from the Cabinet Secretariat, which presides over the Sites of Japan’s Meiji Industrial Revolution: Iron and Steel, Shipbuilding and Coal Mining, a set of relevant World Heritage sites in Japan.

But Manabu Arima, a Japanese history specialist and director general of the Fukuoka City Museum, is not so sure.

“The reason Hashima was introduced as a symbol of (Japan’s) industrial revolution era is its warship-like appearance,” he said. “Measures to prevent deterioration should be … implemented as soon as possible.”