This hydrographic risk assessment allows the Tongan Government, with the support of regional charting authorities, to come to a conclusion about the nature and scope of chart improvement surveys in Tonga. It provides recommendations and conclusions to assist decision makers to prioritise hydrographic surveys in Tonga. These are based on the needs of contemporary shipping for the provision of accurate and adequate nautical charts.
The overall conclusion, based on evidence of economic growth, as well as vessel transit risk, is a need for improved charting in some areas of Tongan waters. The findings are supported on grounds of traffic risk and economic growth. The Cost Benefit Analysis (CBA) of the hydrographic survey provides analysis of the economic and safety advantages both for international and domestic coastal shipping in Tonga.