From Ballast Water Treatment Technology. Published on April 5, 2016.
In complete contrast to the situation in the rest of the world, the US has a functioning regulatory system in place but currently not a single treatment system has successfully navigated the full type-approval process.
Under the US regulations, ships with ballast capacities of between 1,500m³ and 5,000m³ have had to comply since 1 January 2014 and all newbuildings have had to comply since 1 December 2013. After that, the system used must be US Coast Guard type-approved, which could involve installing a new BWMS.
As a consequence of the lack of approved systems, the USCG has needed to implement an interim Alternate Management System (AMS) regime that allows treatment systems approved under IMO rules to be used for a period of five years. Granting AMS status is not automatic as each system has to be judged on its merits before the approval is issued. Approvals are generally granted to manufacturers, but it is possible for individual ships to apply as well.