Praising ballast regulations

by Steve Galea | June 20, 2022
a large cargo boat with ballasts

Published in Conservation Letters earlier this year, the study noted that the Great Lakes-St. Lawrence River basin is the world’s most invaded freshwater system, with ballast water from transoceanic shipping responsible for 65% of invasions in the basin since the modern St. Lawrence Seaway opened in 1959.

It also pointed out that early ballast-water regulations applied in 1993 failed to stem the influx of invasives because they were not mandated for all ships.

That changed in 2006 and 2008, however, when Canada and the US, respectively mandated that all transoceanic ships should conduct open ocean saltwater flushing to ensure that partially filled ballast tanks intended for discharge into the Great Lakes contained salt water before entering the seaway. Both governments have strictly enforced the mandate since.

The study’s before-and-after comparisons of total organismal abundance and species richness in ballast tanks revealed a substantial reduction in invasion risk from ships that conducted saltwater flushing.

According to the study, “Since 2006, the rate of discovery of newly established non-native species in the Great Lakes declined by 85% to its lowest level in two centuries. While multiple factors could plausibly contribute to this decline, empirical evidence supports the 2006/2008 ballast-water regulation as the primary cause, highlighting the benefit of internationally coordinated vector control.”

The authors went on to say, “To our knowledge, the 2006/2008 regulation is the only case of a policy intervention that is linked to a massive reduction of the invasion rate of a large aquatic ecosystem… No other equivalent period of time in the documented history of the Great Lakes basin since 1835 has had fewer invaders discovered than the period of 2007−2019, and not since the Second World War has there been as few ballast-water invasions recorded over a 13-year period.”

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  1. Don Mitchel wrote: To satisfy ballast water legislation signed into law, The “ final rule”/ regulations and/or lack of regulation appears according to this link, scheduled for February 2023 four years after the release of purposed regulation in 2020 to satisfy the legislation signed into law in 2018 Will it matter what happens in the election for 2024? Sadly the history for addressing ballast water, is a history that follows elections producing few results. Back in 2008 when all the senators were running for President, H.R.2830 was left to die in the senate and the new administration opted for more study, over 4years later and after 2012 reelection we got a weak vessel incidental discharge act called VIDA. Hopefully the EPA will not continue to purpose weakening the existing VIDA, by removal of BMP’s (such as trying to avoid the uptakes of sewage and pathogens etc., which they purposed in 2020) and will additionally add something meaningful for the Great Lakes after purposing nothing. This is legislation that uses Federalism and neglects considering the effects of global warming. It dose not consider, (by design) that all United States citizens who depend on clean water for their life, health, and livelihood should be included as stakeholders. The general public is being left clueless by the media and politicians about the dangers and the permanent destruction to our countries water being exasperated by climate change ballast water presents. The emphasis the EPA places on cost is contrary to President Obama’s amending the invasive species act to reflect the need to consider human health when global warming is a factor. Sincerely, Don Mitchel
  2. Don mitchel wrote: If you are interested in VIDA the following government web site updates the status.