American Cruise Lines plans to double its capacity for domestic coastal cruising by ordering 12 catamarans from a US shipbuilder.

The Connecticut-based shipowner currently has two 170-berth cruise ships and three 90-berth passenger ships that sail along US East and West coasts.

American Cruise Lines, which added eight new ships to its fleet over the past five years, also owns six 180-berth riverboats and four 180-berth paddle-wheel boats for American river voyages.

The “Project Blue" initiative to order a dozen 109-berth sister catamarans from Maryland's Chesapeake Shipbuilding will boost its coastal voyage capacity from 610 to 1,308 berths.

American Cruise Lines did not disclose the financial terms of the deal.

“Project Blue started as a design challenge to create a boat small enough for New England harbours and stable enough for the Alaska Inside Passage, with a draft shallow enough for the Atlantic Intracoastal Waterway,” chief executive Charles Robertson said in a statement.

“These boats can run almost anywhere, and because there will be 12 of them, they will be deployed all over the United States.”

The first two Project Blue ships — the American Glory and American Eagle — are under construction and due for delivery in 2023. They are slated to offer East Coast itineraries.

The Project Blue vessels will feature two dining venues, room service and an “adventure deck” equipped with kayaks and other items dedicated to itinerary activities.

American Cruise Lines resumed sailing in March 2021 after suspending operations for about a year due to Covid-19.