The Portsmouth Naval Shipyard, often called the Portsmouth Navy Yard, is a United States Navy shipyard located in Kittery on the southern boundary of Maine near the city of Portsmouth, New Hampshire. PNS is tasked with the overhaul, repair, and modernization of US Navy submarines. Though PNS is nominally a public shipyard, several corporations (e.g., Delphinius Engineering of Eddystone, PA; Oceaneering International of Chesapeake, VA; Orbis Sibro of Mount Pleasant, SC; and Q.E.D. Systems Inc. of Virginia Beach, VA) carry out the submarine maintenance and upgrades there, according to public contract announcements.
