Ballast Water Problem: Current Status and Expected Challenges

Abstract

Transporting non-native species in ballast tanks has been a major challenge over the years. The number of surviving species in the host environment is quite small compared to those of all introduced. However, even a single species can cause great harm to the environment, economy, and public health. Ballast water treatment issues are difficult and complex as the performance of the treatment is highly affected by the variable characteristics of the seawater. In addition, targeted organisms are in a wide spectrum. The International Convention on the Control and Management of Ship Ballast Water and Sediments requires ships to manage ballast water with a Type Approved System in compliance with the Ballast water discharge standard defined in the Convention. The Ballast Water Management Systems Approval (G8) Guide was revised in 2016 and accepted as the BWMS Code (Ballast Water Management Systems Approval Code) as the mandatory regime in 2018. According to the implementation schedule of this mandatory approval regime, the ballast water management system installed on or after 28 October 2020 must be type-approved according to the IMO’s revised G8 requirements. Several systems use different methods with their limitations. However, the ballast water problem does not seem to end only with the installation of the systems on ships. Although substantial international progress has been made in ballast water management (both technically and regulatory), there are still several issues regarding effectiveness, compliance monitoring, and the environment.