Ballast Water Technology: Getting the Numbers RightThe G8 guidelines that define the type approval process for ballast water treatment systems w...
Published on by Water Network Research, Official research team of The Water Network
The G8 guidelines that define the type approval process for ballast water treatment systems were initially agreed at the IMO before any systems had actually been developed.
The IMO had already been working on the issue of invasive species being transferred around the world in ballast water for a couple of decades. It was on the radar back in the 1970s. At MEPC 31 in 1991, the IMO adopted voluntary guidelines that focused on non-release of ballast water, ballast water exchange or discharge into shoreside reception facilities. Onboard treatment systems were mentioned as a possibility for future research.
In the years after the adoption of the Ballast Water Management Convention in 2004, treatment systems grew in type and number, and over 80 gained type approval. However, G8 specified a limited salinity range for testing these systems, and there were no requirements to test with fresh water or different water temperatures. Concern had also been raised about the need to only monitor the effectiveness of the disinfection process for five days. In any case, G8 was only guidance and results could reflect the individual nature of the test water obtained near a particular testing house.
Then the US Coast Guard refused to embrace treatment that rendered organisms permanently non-viable although not necessarily dead. This caused OEMs that use UV treatment to meet two different standards to gain global approval for their systems.
Fast forward to MEPC 81 in March this year, six months before all ships have to comply with the D-2 standard (requiring treatment rather than just exchange), depending on survey anniversary, and the details are still being resolved. After much discussion and three rounds of votes, text for the interim guidance for ships ballasting in challenging, high sediment water was finally approved.
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https://www.marinelink.com/news/ballast-water-technology-getting-numbers-516167Taxonomy
- Ballast Water