A recent National Research Council (NRC) report recommends establishing “benchmark discharge standards” for controlling ballast-water discharges from ships. Requested by EPA and the U.S. Coast Guard, the report states that ships’ uptake and release of ballast water and associated sediment is one of the most prevalent ways non-indigenous invasive species are introduced into new areas. Titled “Assessing the Relationship Between Propagule Pressure and Invasion Risk in Ballast Water,” the report is available for purchase from The National Academies Press.

NRC was not asked “to propose specific ballast water discharge limits”; rather, its task was to “evaluate the risk-release relationship in the context of differing environmental and ecological conditions.” The agencies will use its findings “to help inform the derivation of numeric limits in ballast water for their regulatory programs.” The report recommends that ballast-water discharge standards be based on models that can be tested, compared and updated as necessary to incorporate the latest risk-release data.