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About ACB-1

Inchon Landings

General MacArthur Inchon 1950

          Amphibious Construction Battalion ONE was originally commissioned at Camp Peary, Williamsburg, Virginia, on July 16, 1943 as the 104th Naval Construction Battalion.  During WWII, the 104th was stationed in many locations included Camp Endicott in Gulfport, Mississippi in 1943; Gamododo, New Guinea, and Australia in 1944; and Leyte, Philippine Island, 1945.  During these two years, the 104th completed numerous land based construction projects ranging from an airfield on Los Negros in the Admiralties to a Naval Operating Base on island of Leyte in the Philippines.  The battalion was eventually deactivated in Dec 1945.

           In January 1947, the 104th was reactivated and first began their Amphibious mission when the unit was tasked with "the assembly and placement of pontoon structures, beach rehabilitation, harbor development, salvage, and training of reservist in these operations. " In October 1950, it was recognized by the Chief of Naval Operations that the 104th and 105th NCB were unique units with specialize capabilities that separated them from the rest of the Naval Construction Battalions so they were renamed Amphibious Construction Battalion One and Two.

In the years since, PHIBCB ONE has participated in every major conflict that faced the nation:

          During the Korean War several detachments were deployed to the Western Pacific in support of amphibious operations.  In the September 1950 invasion of Inchon a pontoon causeway was brought into Inchon Harbor on D-Day plus 1 to be used a tide level landing.  General MacArthur came ashore over this pier on D plus 2.


Pontoons at Inchon

Pontoon at Wolmi


pontoon at Inchon

Jeep at Wolmi


            During the Vietnam Conflict, the battalion was the first Seabee unit ashore in the Republic of Vietnam sending detachment to Chu Lai, Da Nang, Hue, and Cua Viet.  Projects undertaken in these locations included installing causeway piers, fuels systems, a mono-mooring fueling buoy, building ammo-pontoons and other special purpose structures.

           In August 1990, PHIBCB ONE was the first Naval Construction Force (NCF) unit to deploy to Saudi Arabia in support of Operation Desert Shield.  The Battalion assisted in the successful offload of the ships from Maritime Prepositioning Squardrons TWO and THREE in support of the First Marine Expeditionary Force and provided some limited technical support to other joint units operating in the area.

           In August 1994 and again in August 1995, the command deployed the Offload Preparation Party (OPP) for Maritime Prepositioning Squadron TWO in support of Operations Valiant Warrior and Vigilant Sentinal in the Persian Gulf due to the threat of resurgence of Iraqi aggression.  In each case the personnel returned home after a couple months but were in a 48hr standby until March 1996.

           Most recently, in January, 2003 ACB-1/2 was deployed to Kuwait Naval Base, Kuwait in support of Operations Enduring Freedom and Iraqi Freedom.  Moving over 1,200 tons of cargo, on 9 C-5 Galaxy aircraft, the PHIBs constructed the largest LSA in ACB history, housing over 4,500 personnel.  Additionally, ACBs were instrumental with the complete download of 13 MPF ships encompassing three MPSRONs.  ELCAS-M was also deployed to move thousands of ammo containers from ship to shore.  A small detachment from ACB-1 also moved forward in Iraq to assist the NMCBs with the anchoring of a floating bridge.

Awards and Recognition

           In recognition of outstanding services rendered in the Korean Conflict, personnel of the Battalion received three Bronze Stars, eight Navy Commendations with Combat "V"s, the Presidential Unit Citation, the Korean Presidential Unit Citation, and numerous letters of recognition for meritorious services.  During the Vietnam Conflict, the Battalion was awarded the Navy Expeditionary Medal, the Vietnam Service Medal, and the Meritorious Unit Citation.  Additionally, the command was awarded a Secretary of the Navy Letter of Commendation for meritorious service from 1994 to 1996.

Current Mission:

           The primary mission of PHIBCB ONE is to provide ship to shore transport of fuel, materials, equipment and water in support of the Amphibious Ready Group (ARG), Marine Expeditionary Force (MEF), and Maritime Prepositioning Force (MPF) operations.  The Battalion provides barge ferry operations, camp support, perimeter defense and limited construction support for these operations.

           The secondary missions are to assist the shore party in operations which do not interfere with the primary mission, and to undertake logistic construction projects and training within the capabilities of assigned personnel and equipment.

WWII Amphibious Seabee History / Achievements:

           During World War II, Amphibious Construction Battalion were designated Naval Construction Battalion, Pontoon, NCB (P), and were generally called Pontoon Operating Battalions.  The importance and impact of these units was demonstrated during the invasion of Siciy where it was proven that pontoon causeways provide an excellent method of rapidly unloading vehicle-borne cargo from Tank Landing Ships (LST).  The shallow waters of the southern beaches of Sicily prevented LST's from moving in close enough to shore to discharge troops and cargo.  Consequently, the enemy made preparation for an assault from the North, where the water was deeper.  By using causeways to connect LST's and the shore, the allies were able to land on the southern beaches, thus achieving the element of surprise.

           After the success of the pontoon systems in Sicily, Pontoon Operating Battalions and Detachments participated in every major invasion in the Atlanic and Pacific theaters of operation.  Pontoon barges and causeways were an important factor in successful amphibious operations in the Pacific Theater beginning with the Kwajalein invasion in early 1944.  By the end of the war, the causeway, pontoons, rhinos and other variations of the Seabee' magic boxes made the difference in the landings at such places as Normandy, Italy, Saipan, Iwo Jima and the Philippines.  Additionally, barge mounted cranes performed an important function in loading and unloading vessels at numerous invasion sites.


ACB-1 Today

ACB-1 Today


Command Philosophy

A - Always ready to answer the call - our people trained and prepared, physically, and mentally; our craft and equipment properly maintained.

C - Competence in our trades, seamanship and defensive combat skills.

B - Bring out the best in our Sailors - as a unit, teams, and individuals.

O - One team - one fight, with every Sailor respected, every Sailor accountable.

N - Never compromise on safety; make ORM your first consideration and your second nature.

E - Excellence in all we do - reflect pride in who you are and what you represent.

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Commander, Amphibious Construction Battalion (ACB) 1
San Diego, CA
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