Reinforcing soft seabed at Henoko in Okinawa could delay U.S. Futenma base move by years

NAHA, OKINAWA PREF. – Construction of a facility to replace the controversial Futenma air base in Okinawa Prefecture may be delayed further due to seabed reinforcement work at the Henoko site after engineers discovered areas of the surrounding ocean floor were softer than originally determined, a source said Wednesday.

Completion of the base in the Henoko coastal area of Nago, where reclamation work is underway, could be pushed beyond the fiscal 2022 target due to the additional work needed.

The Defense Ministry now estimates it could take three years and eight months to improve the seabed at the planned landfill site for the construction of the facility that would replace U.S. Marine Corps Air Station Futenma in Ginowan, according to the source.

The new findings make the chance of achieving the targeted timeline even more difficult and the return of the current Futenma site to Japanese control could be pushed back to the mid-2020s or later.

Tokyo and Washington agreed in April 2013 that the land used for the Futenma base would be returned to Japan in “fiscal 2022 or later,” but the Defense Ministry has said it will be difficult to keep to the schedule due to the wrangling between the central and local governments over the issue.

Many residents have long been frustrated with noise and crime linked to the heavy U.S. military presence in the prefecture and want the Futenma base moved outside of Okinawa.

In the reinforcement work, the Defense Ministry is planning to drive piles of sand into the sea bottom up to a depth of 70 meters below the sea surface.

The ministry, which plans to reclaim some 160 hectares of land in waters off the Henoko area and construct two 1,800-meter runways in a V-shape, has said the total base relocation costs would amount to at least ¥350 billion ($3.14 billion).

But the Okinawa Prefectural Government led by Gov. Denny Tamaki, an opponent of the base transfer plan, has unveiled its own estimate that they could reach ¥2.65 trillion, including ¥150 billion for the seabed reinforcement alone.

The local government has also insisted that it will take 13 years for the new base to start operation, saying it will take five years each for the completion of the seabed improvement and reclamation work before new base facilities can be built.

The central government has been pushing ahead with the base relocation plan as “the only solution” for eliminating the dangers posed by the Futenma base without undermining the deterrence provided under the Japan-U.S. security alliance.

In a nonbinding prefectural referendum in February, more than 70 percent of Okinawa voters rejected the relocation plan.