Prefectural surveys have found that precautionary measures need to be taken at about 295,000 locations to deal with landslides, but more than 20 percent have not yet been officially designated as needing such measures, The Yomiuri Shimbun has found.
About 14,000 spots have been left undesignated for more than two years since the surveys were conducted by prefectural governments. The high number is chiefly due to prefectural governments' difficulty in winning the approval of local municipalities and residents for the designation.
In Wakayama Prefecture, recently battered by Typhoon No. 12, about 70 percent of the locations found to need designation have not yet been recognized.
Prefectural governments survey areas deemed in danger of landslides, including their geographical features, based on the law enacted in 2001 concerning prevention of landslides.
If an area is found to need such measures as establishing an evacuation system, the prefectural government will designate the location as needing precautionary measures after hearing the opinions of local municipal leaders.
When an area is designated, the local municipal government has to establish a community wireless system and devise hazard maps showing possible landslide areas, so as to make residents aware of the danger.
The Yomiuri Shimbun learned from interviewing prefectural governments that surveys had been conducted at about 310,000 locations as of the end of August. About 295,000 of these were found to need designation as areas requiring precautionary measures.
Of the 295,000 locations, about 65,000 were still undesignated, with some locations still undesignated even though they were surveyed seven years ago.
Saga Prefecture had the highest percentage of undesignated spots: 2,512 out of 3,065, or 82 percent.
In Wakayama Prefecture, where the recent typhoon left 74 people dead and 21 people missing, 3,024 out of 4,330 locations found to need the designation were yet to be designated. At one such place, a man was killed in a landslide during the recent typhoon.
In Nara Prefecture, 4,144 out of 8,595 locations found to need the designation had yet to be designated.
Regarding reasons for the delay, officials of the Saga, Wakayama and Nara prefectural governments said they had to spend a great deal of time explaining the matter to municipal governments and residents and coordinating opinions with them.
An Oita prefectural official said it had yet to win consent from local residents, as they feared such designations will reduce the value of their land.
According to the Land, Infrastructure, Transport and Tourism Ministry, 227,804 locations had been designated by the ministry as needing precautions against landslides as of the end of August, and 107,963 spots had been designated as needing special precautionary measures.
"As designations are being made mainly by prefectural governments, we can't instruct or force local municipalities to take precautionary measures. Nonetheless, it is not desirable to postpone the designation, as it will hinder the evacuation of residents during disasters," an official of the land ministry said.
The law concerning the prevention of landslides was enacted following the torrential rain that induced landslides in Hiroshima Prefecture in 1999, killing 24 people.
Once designated as needing precautionary measures, a local government has to make its residents aware of the danger and improve its evacuation procedures for residents.
When designated as needing special measures--as a result of being particularly susceptible to landslides and greater damage expected--restrictions are placed on the development of residential land and building structures.
(Sep. 30, 2011)