Frequently Asked Qs: 3.11 Tsunami Debris

The tsunami triggered by the Great East Japan Earthquake of March 11, 2011 (‘3.11 Tsunami’), washed out houses, shipping containers and other various items from land, and other things at sea such as fishing vessels and fishing gears; then it pushed them to offshore. Driven by ocean currents and winds, most of them have drifted eastward. Presumably some are still drifting (3.11 Tsunami Debris), although the others have already sunk.

Since the 3.11 Tsunami Debris was making large patches right after the 3.11 Tsunami, Government of Japan (GOJ) received many reports of at-sea sightings from vessels. However, the number of such reports has been dramatically decreased since the fall of 2011. GOJ supposes that this is because, as time passes, the debris has dispersed and some of them have sunk.

GOJ has been working on this issue by estimating total amount of the Debris, assessing current situation, and predicting the Debris’ trajectory in cooperation with experts, while sharing information and communicating with relevant countries.

Here are answers to frequently asked questions about the 3.11 Tsunami Debris.

About Tsunami Debris

Q1: How much is the total amount of the 3.11 Tsunami Debris?

A1:
The amount of the floating debris at the immediate aftermath of the Earthquake is estimated to have been about 1.5 million tons. Since then, however, some of the 1.5 million tons of debris is considered to have been collected or to have sunk already. Therefore, the amount of floating debris still drifting at this point is considered to be less than 1.5 million tons.

It is estimated that the Great Japan Earthquake generated more than 20 million tons of debris in the three affected prefectures (Iwate, Miyagi and Fukushima prefectures). Out of the 20 million tons, about 5 million tons of debris is estimated to have been washed out by the 3.11 Tsunami. 70 percent of the 5 million tons (3.5 million tons) of debris is considered to have deposited on seabed along Japan’s coast, and remaining 30 percent (1.5 million tons) is considered to have become floating debris at the immediate aftermath of the Earthquake. Since then, however, some of the 1.5 million tons of debris is considered to have been collected or to have sunk already. Therefore, the amount of floating debris still drifting at this point is considered to be less than 1.5 million tons.

Q2: What is the 3.11 Tsunami Debris composed of?

A2:
It is estimated that more than 90 percent of the floating debris caused by 3.11 Tsunami is parts of collapsed houses and driftwoods. The 3.11 Tsunami washed out collapsed houses, cars, woods, ships, aquaculture facilities, fixed fishing nets, cargo containers, etc. More than 90 percent of the floating debris is parts of collapsed houses and driftwoods, which are difficult to sink.

Q3: What is the trajectory of the 3.11 Tsunami Debris? When and Where do they reach?

A3:
The latest result of the prediction, which was published March, 2013, says that comparatively high density parts of broken houses and half-submerged fishing vessels, which most of floating Debris consist of, is expected to reach near-shore of west coast of North America from around April 2013. Some debris may travel faster/slower and arrive earlier/later than others, because impact of westerlies on the drifting speed of the debris may differ depending on shapes and conditions of the debris.

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Q4: Is it possible that any debris carried out to sea by the tsunami is radioactive?

A4: For the following reasons, it is the view of the Government of Japan that any tsunami debris is highly unlikely radioactive:

  • A) Most tsunami debris was already far out at sea by the time that the Fukushima Dai-Ichi Nuclear Plant accident occurred.
  • B) Even if radioactive material released from the nuclear plant contaminated some tsunami debris, one of the main substances of radioactivity ? radioactive cesium ? would most likely have been washed away altogether by ocean waves and rain.
  • C) Another main substance of radioactivity released during the incident ? radioactive iodine ? has the short half-life of eight days and is therefore likely to be at undetectable levels. For the reasons mentioned above, again, it is extremely unlikely that any tsunami debris is radioactive, and thus surveys on radioactivity of tsunami debris have not been conducted.
    In the case that the Government of Japan becomes aware of radioactive tsunami debris based on scientific evidence, including reports from other countries, concrete measures to respond will be considered on a case-by-case basis.

Q5: Would the 3.11 Tsunami Debris have negative impact on navigation and marine life?

A5:

  • A) Navigational Hazard Based on the information from vessels, no particular navigational hazard has been reported so far.
  • B) Impacts on the marine ecosystem
    No specific problem has been reported so far. If there is such a report, GOJ would consider how to respond.
  • C) Impacts on the fishing industry
    No specific problem has been reported so far. If there is such a report, GOJ would consider how to respond.

Q6: What should I do if I find property of value, such as jewels, or personal items, such as personal photo albums, at the beach etc.?

A6:
The possibility is considerably low that property of value or personal items whose owner is readily identifiable among the 3.11 Tsunami Debris will wash up in foreign countries. With this in mind, if you find any object (1) that is from Japan, (2) whose owner is readily identifiable and (3) that is considered as property of value or personally important item (e.g. Jewels and personal photo albums in a vessel that washes up), please contact your country’s authorities such as police. (GOJ has requested the governments of relevant countries to contact the Japanese Embassies or Consulates if the government receives a report on such an object and considers it meets these three conditions.)

Q7: Will bodies arrive at my country?

A7:
It appears quite unlikely that the bodies of victims of the 3.11 Earthquake and Tsunami will arrive at foreign countries, except the cases that they arrived together with drifting vessels. Additionally, the Japan Coast Guard conducted searches the interiors of a certain number of drifting vessels in the wake of the Earthquake.
If you find bodies at the beach etc., whether or not it appears to have resulted from the Earthquake, please immediately contact your local police.

About GOJ actions against Tsunami Debris

Q8: What is GOJ doing about the 3.11 Tsunami Debris?

A8:
The Interagency Team coordinated by the Secretariat of the Headquarters for Ocean Policy of the Cabinet Secretariat is addressing this matter. The specific measures are the followings;

  • A) Assessing current situation by collecting information from navigating vessels
  • B) Estimating total amount of the Debris (Details of the estimation)
  • C) Developing simulation models to predict the trajectory of the Debris (Details of the prediction)
  • D) Sharing information and exchanging opinions between Japanese and the U.S. governments and experts

Considering the results of these estimation and prediction, GOJ will continue to share information and have consultations with related countries and institutions, and deliberate the additional actions.

Q9:
What steps are being taken by the Government of Japan in response to tsunami debris that has washed up on shore or is still drifting at sea?

A9:
The debris that was carried out to sea by the tsunami following the Great East Japan Earthquake is a matter of concern for Japan, too.
On the occasion of the APEC Economic Leaders’ meeting (Sep. 8, 2012),Prime Minister Yoshihiko Noda informed the United States and Canada that GOJwould make a financial contributionof atotal of 6 million U.S. dollars (5m U.S. ＄ to U.S. and about 1m Canadian＄ to Canada) as a token ofgoodwill.
In December 2012, Japan made a financial contribution of 5 million U.S. dollars to the United States. GOJ also exchanged diplomatic notes regarding this matter with the Government of Canada in March, 2013. We are cooperating with the appropriate government agencies of the United States and Canada that have coastal areas where tsunami debris has washed up or may arrive by sharing information in an expeditious way and maintaining effective channels of communication.

Q10: How has Japan been cooperating with other governments in responding to and disposing of tsunami debris that has washed up on shore or is still drifting at sea? Which Japanese and foreign government agencies are involved in this effort?

A10:
In Japan, the Cabinet Office’s Secretariat of the Headquarters for Ocean Policy is taking the lead in preparing documents and providing information useful to the United States, Canada and other coastal countries which can be affected.
In the United States and Canada, Japanese diplomatic missions have been working closely with federal and state government agencies including NOAA, promptly responding to requests for information and providing necessary results. Furthermore, experts from Japan, the United States and Canada have been holding discussions on various topics including computer simulations being conducted by the Japanese Ministry of Environment to predict the flows of tsunami debris.
Japan intends to continue cooperating with the relevant countries in various ways by sharing information in an expeditious way while maintaining effective channels of communication.

Q11:
What concrete measures is the Government of Japan planning or taking to cooperate with relevant countries?

A11:Japan has been receiving and responding to requests for information from the United States and other countries. We have also been taking several actions such as providing information onTsunami Debris, announcing coastal cleanup events in these countries and assisting NGOs’ activities.
We continue to consider other measures on the basis of ongoing cooperation with the United States and other countries.

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Q12: What arrangements have been made for notifying the owners of items of personal value that are found among washed-up debris? Will the Government of Japan take steps to facilitate contact between those who find such items and their owners?

A12:
The Government of Japan is looking at what it can do to help facilitate the return of items of personal value which can be confirmed as tsunami debris and whose belongings.

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