IG report details mold, failing pipes and deteriorating facilities at US bases in Japan

YOKOTA AIR BASE, Japan — A Defense Department Inspector General review found widespread infrastructure problems at U.S. bases in Japan, including moldy housing, failing water lines, deteriorating concrete and maintenance and storage facilities in need of repair.

Inspection teams visited 11 U.S. installations in the Pacific in May 2025 and documented issues at Air Force and Marine Corps facilities on Okinawa and at Yokota in western Tokyo, according to a heavily redacted, 48-page report dated Aug. 6.

“We found maintenance and storage infrastructure concerns at [Yokota and Kadena Air Base, Okinawa] such as visible corrosion, visible cracks on the building exterior and interior, visible concrete spalling and exposed rebar, asbestos-containing material, and facilities that did not meet facility requirements,” the report states.

Mark Sinder, deputy assistant secretary of defense for infrastructure modernization and resilience, recommended that installation commanders submit prioritized lists of infrastructure projects through U.S. Forces Japan and Pacific Command by Oct. 26.

Yokota — headquarters for USFJ, 5th Air Force and the 374th Airlift Wing in western Tokyo — has already addressed some of the problems, said a statement emailed Wednesday by Army Col. Abigail Cathelineaud, the USFJ command engineer.

“Work is actively underway to address the facility challenges highlighted in the August 6 [Department of Defense] IG report,” she said. “The safety and quality of life of our service members and their families is our top priority.”

The report attributed many of the problems to aging facilities, recurring typhoons and earthquakes, personnel shortages, high construction costs and uncertainty over how projects are funded.

It also noted that Japanese government funding generally supports larger strategic construction programs rather than routine repairs.

Images received by the Department of Defense Inspector General on Aug. 4, 2025, show underground pipe failure and flooding at the natatorium on Yokota Air Base, Japan. (Department of Defense)

At Kadena, inspectors documented problems at Building 400, which had been vacated as unsafe. The roof held about 8 inches of standing water, while inspectors found concrete spalling and water intrusion throughout the structure.

Spalling occurs when pieces of concrete crack, flake or break away, sometimes exposing reinforced steel.

The report documented hundreds of housing problems at Kadena’s Stearley Heights, Sebille Manor and Washington Heights neighborhoods and at Kinser Tower on Marine Corps Camp Kinser.

Seventy-five housing units had been vacated because of mold, concrete spalling or both.

Nearly 1,000 housing units were affected by concrete spalling alone, while hundreds more had mold or a combination of the two problems, according to the report.

Kinser Tower had 544 units affected by spalling, the largest number recorded at a single location.

The Okinawa Military Housing Office delayed repairs at Camp Kinser housing in October after asbestos was discovered during renovation work.

Inspectors also identified significant problems with Kadena’s water system, although much of the report’s discussion was redacted.

Images received by the Department of Defense Inspector General on July 10, 2025, show corrosion in a hangar at Kadena Air Base, Okinawa. (Department of Defense)

Images received by the Department of Defense Inspector General on July 10, 2025, show the aftermath of two roof collapses at Kadena Air Base, Okinawa. (Department of Defense)

Images received by the Department of Defense Inspector General on July 10, 2025, show holes and corrosion on a hangar at Kadena Air Base, Okinawa. (Department of Defense)

Images received by the Department of Defense Inspector General on July 10, 2025, show crumbling concrete in housing units at Kadena Air Base, Okinawa. (Department of Defense)

Photos and accompanying descriptions show that one 12-foot crack caused a water-line failure that lost approximately 400 million gallons and cost $200,000 to repair. The report did not specify when the break occurred.

Another water-line failure beneath a Kadena taxiway lost more than 4 million gallons and cost $31,000 to repair.

Details of conditions inside the Kadena Munitions Storage Area were entirely redacted.

Kadena’s chapel showed severe concrete spalling and exposed, rusted reinforced steel, according to the report.

At Camp Courtney, also on Okinawa, inspectors found similar deterioration at Tengan Piers, a logistics and recreation facility described in the report as roughly 50 years old and having “reached the end of it[s] service life.”

At Yokota, inspectors noted damage to Building 714, headquarters for USFJ and 5th Air Force, caused by a May 2024 fire. That damage has since been repaired, USFJ spokesman Air Force Col. John Severns said by email Wednesday.

Inspectors also found severe pipe corrosion at the Yokota Natatorium, which closed earlier this year for repairs. One failed pipe had caused flooding.

“The IG report accurately reflects our priorities for facilities, and we are already executing repairs, including the renovations to the Yokota natatorium water system,” Cathelineaud said. “Other major projects, such as renovation [of] the North Housing Area on Yokota, are also underway.”