WASHINGTON — Guam’s government needs more timely information from the Defense Department about the planned transfer of 8,000 Marines and their dependents there from Japan so it can better plan for the necessary infrastructure buildup and financing, a government report out Friday said.

"The government of Guam is expected to be largely responsible for funding and constructing ... off-base roads and utilities and providing certain public services,” said the report from the nonpartisan Government Accountability Office.
The movement of Marines, which is expected to begin next year with preliminary construction, would also require bringing in additional support troops from the other service branches.
If implemented, the transfer would increase the military population on Guam from 15,000 in 2009 to about 29,000 in 2014, and to more than 39,000 by 2020, according to the GAO report. That would increase the island population of 178,400 by about 14 percent over those years, the report said.
The transfer of the Marines would be a huge economic boon for Guam, if it’s prepared to handle the influx and all the jobs the move will create.
It’s estimated the move will cost $15 billion or more and will generate as many as many as 20,000 construction jobs during peak phases, GAO has determined.
But thus far in the planning process, some of Guam’s government agencies have had a difficult time accurately estimating construction and financing costs.
For example, when Guam officials received updated information on some of the road improvements necessary, the cost estimate dropped from $4.4 billion to $1.5 billion, GAO reported.
The Pentagon responded to the GAO report by saying that it is sharing information as soon as it becomes available and that it has planned several consultant studies that should help Guam officials plan better.
The movement of the Marines from Okinawa, Japan, to Guam is considered a critical part of the nation’s Pacific military and diplomatic strategy.
The Japanese government has been under intense political pressure to get the Marines off Okinawa since 1995, when three U.S. servicemen raped a 12-year-old girl there, straining U.S.-Japan relations. In all, the U.S. has about 50,000 military personnel in Japan.
President Obama discussed the move with Japan’s Prime Minister Yukio Hatoyama when they met Friday in Tokyo.
“The United States and Japan have set up a high-level working group that will focus on implementation of the agreement that our two governments have reached with respect to the restructuring of U.S. forces in Okinawa, and we hope to complete this work expeditiously,” Obama said. “Our goal remains the same, and that’s to provide for the defense of Japan with minimal intrusion on the lives of the people who share this space.”