As work continues on reclaiming land in waters off Okinawa for a U.S. military base project, the prefectural government still has a card to play next year in an intensifying battle to halt the project.

The central government is expected to seek approval of a design change for the reclamation work from prefectural officials as was required under the law as early as January.

The change became necessary after it was discovered that a broad swath of soft seabed lies in the planned reclamation area off the Henoko district of Nago in the prefecture.

Blocking the design change appears to be the only option left for the prefectural government to stop the construction of a base that will assume the functions of U.S. Marine Corps Air Station Futenma in Ginowan, also in the prefecture.

The problem of the weak ground, which has been described as having the consistency of "mayonnaise," was not known when the pro-central government Okinawa governor approved the reclamation plan in 2013. The government acknowledged the problem only in 2018.

Protesters of the U.S. military base staged a sit-in on Dec. 10 in front of U.S. Marine Corps Camp Schwab, near where the new facility will be built. Their demonstrations will soon mark the 2,000th day.

But the spectacle of the formidable central government overwhelming a small prefecture in its push to ramrod the unpopular project has rarely changed over recent years.

The central government began pouring earth and sand in a portion of the planned reclamation area on Dec. 14, 2018, amid an Okinawan outcry, marking an advanced phase of the base construction.

The 39.3-hectare parcel represents one-fourth of the entire area to be reclaimed for the base. The central government expects to complete reclamation on that portion in the summer of 2020. The soft ground exists in the other side to the northeast.

Okinawan officials are increasingly anxious in the face of the steady progress in the reclamation work despite repeated pronouncements of their opposition through elections and a referendum in February that saw more than 70 percent of Okinawan voters oppose the relocation of Futenma to within the prefecture.

“I find it extremely frustrating to be unable to promise islanders when I can give an answer to the base question when they are enduring,” said Okinawa Governor Denny Tamaki, who was elected in autumn 2018.

The prefectural government has engaged in a court battle against the central government through two lawsuits to have the base project suspended.

But the outlook is bleak.

2020 A PIVOTAL YEAR

Perhaps the only possibility that Okinawan officials could change the course of the tussle would be through denying a permit to the central government for the design change in the reclamation work covering waters with mushy ground.

Tamaki is set to block the design change.

Okinawan officials assert that the reclamation will be technically infeasible due to the depth of the soft foundation.

But they fear that islanders may gradually resign themselves to the reclamation work as an “existing fact” when they see the daily convoy of trucks unloading soil and sand in the sea to turn waters into land.

“When more and more land is reclaimed, our greatest enemy will be a sense of resignation spreading among Okinawans,” said a member of the prefectural assembly who is allying with Tamaki.

A prefectural assembly election is scheduled for May or June 2020. Currently, 26 assembly members support the governor, while 20, most of who are members of Prime Minister Shinzo Abe’s Liberal Democratic Party and its junior coalition partner, Komeito, are opposed to him.

But some members of the pro-Tamaki forces are retiring and have yet to find successors to run in next year's election.

A change in the power balance of the prefectural assembly is certain to back the governor into a corner.

The constant sight of more land being reclaimed off Henoko could prompt even opponents of the U.S. base project to give up their long fight against the central government.

The central government is trying to bolster the legitimacy of the reclamation of the rest of the remaining area by gaining the endorsement of civil engineers.

In September, the Defense Ministry held the first meeting on technical research in which experts offer advice on the planned work to reinforce the soft ground off Henoko.

“We want experts to settle the dispute over the feasibility of the reclamation to prevent speculation from spreading that the soil improvement work is not viable,” said a senior official with the prime minister’s office.

The ministry selected the members of the meeting based on the opinion of the prime minister’s office, according to a defense ministry official.

In the meeting in November, experts agreed to the feasibility of the reinforcement work when ministry officials gave an estimate that the reclaimed land will sink up to 1.3 meters 50 years after the embankment is put in place in that segment.

The members are expected to meet again this month to affirm that there will be no big change to a private-sector company’s estimate that the base project will take at least 11 years and eight months, including the three years and eight months of soil improvement work.

The Justice Ministry is also preparing for a legal battle to respond to the governor's likely rejection of the design change.

As of 2014, when the existence of soft ground in the seabed was not known, Itsunori Onodera, defense minister at that time, estimated the reclamation costs to reach at least 350 billion yen ($3.24 billion).

Prefectural officials say that the final price tag will balloon to 2.55 trillion yen.

(This article was compiled from reports by Shinichi Fujiwara, Kazuyuki Ito, Ryuichi Yamashita and Ryo Aibara.)