The National Archives of Japan, which houses government documents of historical value — including the Constitution — are in danger of filling up by March 2017.
Officials said Tuesday that the main building in Chiyoda Ward, Tokyo, is already at maximum capacity and a second building in Tsukuba, Ibaraki Prefecture, was 70 percent full as of last summer.
The archives are filling up faster than ever due to a law on the preservation of official state documents introduced in April 2011 that has resulted in a 50 percent increase in materials being stored compared with fiscal 2008.
The law was enacted in response to the loss of numerous national pension records at the now-defunct Social Insurance Agency.
While documents are stored digitally, physical copies are also kept in the two buildings. Officials estimate that if all of the files as of March 2011 were stacked on top of each other, the pile would stand roughly 57 km high.
The Cabinet Office had planned to build more facilities, but this move was dashed by a funding shortfall. In the meantime, the Kansai branch of the National Diet Library in Kyoto will temporarily accept documents once the archives are full.
Materials stored in the archives include the Meiji Constitution and historical texts from the Edo Period.
On Wednesday, Justice Minister Sadakazu Tanigaki, who is also head of the ruling Liberal Democratic Party-New Komeito bloc's national archives storage group, met with Prime Minister Shinzo Abe, urging him to allocate funds next fiscal year to research the issue.