SPC Geoscience Division

Home News & Media Releases Latest Work to Protect Kiribati’s Vulnerable Coastline Uncovers Potentially Explosive Secrets from Tarawa Lagoon

Work to Protect Kiribati’s Vulnerable Coastline Uncovers Potentially Explosive Secrets from Tarawa Lagoon

E-mail Print PDF

16 April 2013 - A survey of the South Tarawa lagoon has revealed some potentially explosive secrets from its past as one of the major battlegrounds of WWII. The survey was designed to identify battle debris that still litters the floor of the lagoon seventy years after the infamous Battle of Tarawa in 1943.

Funded by the New Zealand Regional Ocean Sciences Grant, the survey was undertaken as part of the Government’s work to reduce the atoll’s damaging reliance on beach mining by identifying potential sources of construction aggregate on the floor of the Tarawa Lagoon. The widespread practice of beach mining has been weakening the atoll’s vulnerable shoreline along with Government efforts to protect communities from the worsening impacts of climate change and rising sea levels.

The Government turned to SOPAC, the region’s Applied Geoscience & Technology Division of the Secretariat of the Pacific Community, for guidance on safe methods to dredge an alternative source of sand and gravel from Tarawa’s southern lagoon. Before dredging can begin, as part of the European-Union funded Environmentally Safe Aggregate for Tarawa (ESAT) project, SOPAC first needed to identify any potential problems that might be posed by any unidentified and unexploded ordnance.

During WWII, the islands of Kiribati saw some of the Pacific’s bloodiest encounters.  From 20-24 November 1943, an invasion flotilla of 18,000 US Naval and Marine Corps troops attacked the fortified Japanese garrison on Betio in Southern Tarawa. The 4,600 Japanese defenders fought almost to the last man, and more than 1,000 Americans lost their lives.

SOPAC’s Survey Leader, Geophysicist Robert Smith, is still analysing the data but he has already identified two previously unknown vessel wrecks and unearthed numerous artillery remnants. Of the vessels, Smith says, “These may be sunken Higgins boats, which would have carried 20-30 marines each.” The US government has already expressed a keen interest in Smith’s findings.

The Battle of Tarawa was the first American offensive in the central Pacific. Tragically for US forces, the lagoon was too shallow for the even the 4ft shallow draft Higgins boats which tried to approach the beaches of Betio during a neap tide. According to observers in 1943, troops were forced to approach the beach on foot wadding hundreds of yards or via unarmoured LTV “Alligators.”

Sources suggest that the US military fired or dropped more than 2,400 tons of ordnance onto Betio during the amphibious landings. Failure rates for the ordnance are estimated between 25% and 30%, so it is likely that a large quantity did not explode.

In addition to uncovering this fascinating historical find, the completion of the survey will also bring unparalleled accuracy to new sea floor maps and charts, ensuring safe passage for cargo and transport vessels. This represents both a critical step in clearing the path for successful progress of the ESAT lagoon dredging project and satisfies the needs of the Kiribati Ports Authority for navigation.

According to Smith, “It should be possible to locate areas where the dredge can safely operate, but it will require some very careful follow-up debris removal.”

In this way, the SOPAC project to replace the unsustainable practice of beach mining with more environmentally friendly dredging from the lagoon may also help to diffuse this potentially explosive problem from Tarawa’s violent and not-so-distant past.


For more information on SOPACs Environmentally Safe Aggregate for Tarawa (ESAT) Project please contact Molly Powers at This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Photo Caption: SOPAC technicians Peni Musunamasi and Roqica Donato carry out metal detection as part of the UXO survey  in South Tarawa Lagoon. (photo credit: Robert Smith)

Video: TVNZ One News

Last Updated on Thursday, 23 May 2013 08:52  


Pacific Island countries are amongst the most disaster prone in the region, exposed to natural hazards such as floods, droughts, tropical cyclones, earthquakes, volcanic eruptions and tsunamis, which all pose a significant challenge to development in the Pacific region. A single disaster event can result in losses in the millions of dollars and can undo progress in areas such as infrastructure, agriculture, healthcare and education.

Despite recognition of the importance of disaster resilient approaches to development, many countries face challenges in identifying ways to effectively mainstream risk reduction considerations into national development planning processes. To address this, the Secretariat of the Pacific Community, in partnership with the Asian Disaster Preparedness Centre is holding a one week training workshop which focusses on how to mainstream Disaster Risk Reduction into development.

The training, in Nadi from 14-18th July, includes participants from the Cook Islands, Fiji, Samoa, Solomon Islands, Tonga and Vanuatu with representatives of National Disaster Management Offices and ministries responsible for national planning and finance. Representatives from the Pacific islands Forum Secretariat, Secretariat of the Pacific Community, Secretariat of the Pacific Regional Environment Programme and United Nations Development Programme will also participate in the training workshop.