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Naval Mobile Construction Battalion (NMCB) 18
NMCB-18 Menu


Naval Mobile Construction Battalion Eighteen can trace its history back to the Second World War when construction men began government-sanctioned military training to be able to defend themselves and their project sites in the Pacific Theater of war. In late July 1942, hundreds of officers and enlisted men were gathered together in Camp Allen, Norfolk, Va. They would go through Boot Camp together and by August 10, the 18th Naval Construction Battalion was formed. That same day the troops held their first Battalion Parade where the battalion colors were presented and senior officers introduced.

While at Camp Allen the newly formed battalion was assigned to the 2nd Marine Division, in accordance with the request of the US Marine Corps that a Naval Construction Battalion be assigned to each Marine Division. On August 11, 1942, the battalion was moved to Davisville, R.I. where the troops saw their first liberty.

In order to streamline construction battalions to conform to the triangular organization of the Marines, the construction battalions were asked to separate one company and one-fourth of Headquarters Company, to serve as replacement groups. In accordance with this design, Company “C” reinforced was separated from the rest of the battalion and departed for the west coast on 6 September.

Five days later, the battalion proper left Rhode Island and returned to Norfolk, Va., setting up shop at Camp Bradford. It was here that permanent staff positions were filled, Navy uniforms were mailed home, and where the new Seabees donned the uniforms worn by their colleagues in the Marine Corps. Construction equipment from across the country was transported to the Norfolk docks and staged for loading aboard cargo ships bound for the South Seas.

On September 19, 1942, the Seabees of 18th Naval Construction Battalion boarded the USS Kenmore, and began their lengthy journey to the Islands of the Pacific. After two months of training, the men were looking forward to seeing action and watched in anticipation as the various milestones were checked off their calendars. They stopped at Guantanamo Bay, Cuba, to increase their weapons familiarization skills on the Marine’s rifle range. The ship also pulled into Panama, yet no liberty was authorized at the time; the need for men and materials in the Pacific was a top priority at the time.

On Armistice Day, the Kenmore pulled into Noumea, New Caledonia where all personnel, save Company “B”, disembarked and made camp on the shore. Most of the battalion would remain in Noumea for nearly two weeks performing smaller construction projects they knew they could complete given so short a timeframe. Company “B”, who had not left the ship, moved forward and arrived on Guadalcanal in the Solomon Islands on December 3. This advance party helped set up the camp and base facilities that the remainder of the battalion would occupy and use once they arrived nine days later.

On August 7, 1942, the 2nd Marine Division had landed on Guadalcanal, initiating the first Unites States land offensive in the Pacific. This battle would prove to be a decisive turning point of the war as it provided the Allies with a base in which to launch further invasions of Japanese-held islands. Taking the island was the job of the Marines; making it into the base so desperately needed was the job of the Seabees.

After celebrating Christmas together, the battalion undertook their first large-scale operation, the construction of a lengthy airfield, complete with a small airport capable of sustaining air operations in the region. Amidst extreme rainstorms, tropical heat, continual air raids, and a challenging deadline, the Seabees of the 18th Naval Construction Battalion proved they could deliver an incredibly valuable commodity in a timely and efficient manner. The first aircraft was able to take off only sixteen days after construction began. Twenty-eight days later, multiple aircraft were patrolling the skies over Guadalcanal as a direct result of the efforts of these first Seabees.

The Commanding Officer and Executive Officer were awarded the Legion of Merit for their leadership skills so clearly demonstrated on the island and the battalion as a whole quickly gained a reputation as a construction force to be reckoned with. So impressed were the Marines on Guadalcanal that they kept the Bees longer than initially planned, tasking them with creating roads, improving existing ones, and within a month, turning the improvement and maintenance of all of the airfields on the island over to the battalion.

Although the 2nd Marine Division departed Guadalcanal in February of 1943, the members of the battalion remained behind for two additional months, all the while making improvements upon the structures and facilities they had initially erected. They finally boarded a ship and made ports of call at Espiritu Santo, New Hebrides and Noumea, New Caledonia, before rejoining the division in Wellington, New Zealand.

The battalion would spend the next half a year in intensive training, all leading up to some great enterprise that they were told they’d soon undertake. During this training period the men were permitted occasional liberty and it was said that the hospitality of the local inhabitants coupled with the scenic wonders of the island were among the veterans’ fondest memories of the war.

Having secured Guadalcanal, the 2nd Marine Division turned their attention to using it to make further advancements into enemy-held territory. The Gilbert Islands became the focus of this advance and the Tarawa Atoll in particular held strategic advantages for the Allies. On November 20, 1943, the Marines landed on Tarawa and paid a heavy price for every acre of territory they gained. An extended reef that had been underestimated proved to be a serious hazard to navigation and the landing craft were forced to offload the Marines hundreds of yards from the beaches.

Roughly two-thirds of the battalion actively participated in the taking of Tarawa. The Navy awarded the Presidential Unit Citation to the 2nd Marine Division, but as the 18th Construction Battalion was cited as the 3rd Battalion of the 18th Marines (at the time their official designation), only those Seabees actually taking part in the operation were entitled to wear the coveted ribbon.

The principal challenge assigned to the members of the 18th was the hasty repair of the Japanese airfield of Betio. A day and-a-half after receiving the assignment, Seabees had their plans in place and set about completing their mission. Under sporadic sniper fire and suffering a severe shortage of equipment, they managed to complete enough repairs to permit emergency landings should they be needed. Very early on in the work, two planes were forced to make such a landing at Betio, one of which crash landed, necessitating a salvage operation as well as repair work to the damaged field.

After two months on Tarawa, the battalion was moved to the rear echelon with the 2nd Marine Division on the Big Island of Hawai’i. Here they encamped on Parker Ranch, the country’s largest privately-owned ranch. The following four months were spent performing camp maintenance, improving roads, and upgrading a nearby airport, all within the high-altitude valley nestled between Mauna Kea and Mauna Loa Mountain. They also began training in earnest; all with the understanding that the next objective of the war would soon be revealed to them.

The island-hopping campaign of the Pacific theater was in full swing when the Navy recognized the need for advanced air bases throughout the South Pacific. As a result, the Mariana Islands were invaded in June and July of 1943. When the 2nd Marine Division was ordered to invade Saipan, the 18th Construction Battalion departed Hawai’i with them.

When the Seabees landed on Saipan immediately following the initial assault waves, they demonstrated the second portion of their credo, “We Build; We Fight.” Although the Seabees had engaged the enemy before, within their own camp boundaries on Tarawa, they had never before so clearly demonstrated the fulfillment of their credo than on the island of Saipan. They were forced to dig in to the beaches that the Japanese were concentrating mortar fire upon. They set about unloading supply ships and on several occasions, rooted out Japanese soldiers who were hidden in dugouts that had been passed over by the initial wave of invading Marines. When a call came for volunteers to take provisions to the front lines, armed working parties filled up with ranks of Seabees from the 18th.

The Bees additionally worked on larger construction projects, most notably a hospital whose construction was continually interrupted by sniper fire. All of this work was performed while the troops lived in shelter-halves and subsisted on “C” and “K” rations. Hobo shacks constructed of Japanese scrap metal were eventually erected, but the veterans of the battalion would always recall with pride the hardships they shared under the ever-present threat of enemy fire.

After the operation on Saipan, the Marines and their trusted Seabees were transported to the island of Tinian, another strategic piece of real estate among the Mariana Islands. Here they were tasked with constructing a large-scale B29 base and supporting structures. Homing towers, runways, and base facility improvements were all handled in a timely and efficient manner, adding to the battalion’s growing reputation as an accomplished construction force. What impressed the Marines the most was the Seabees’ ability to make do with the limited resources at their disposal. Due to an oversight, the majority of their earth moving equipment did not arrive on Tinian until the rear echelon arrived. Yet the Seabees continued to meet one aggressive deadline after another.

The battalion would spend the remainder of the war on Tinian, building up the extensive base that had already been constructed. With over thirty-two months spent overseas in support of the war, an unparalleled record of construction achievements and with participation in four combat operations, the members of the 18th Construction Battalion helped establish in the public’s mind what the Seabees were all about and what they could accomplish under conditions of hardship and deprivation.

The battalion remained on Tinian until they were decommissioned on June 20, 1945. About one-third of the Seabees were returned to the States for discharge or rehabilitation. The remainder were transferred to other battalions on Tinian.

In June 1960, the Chief of Naval Operations authorized the establishment of eighteen Reserve Naval Mobile Construction Battalions (RNMCB). The 18th NCB was re-commissioned as Construction Battalion Command 18 on March 31, 1962. Later that year, the battalion was redesigned RNMCB 18. The staff of RNMCB 18 began meeting monthly in Building 27 at the Naval Base, Seattle, Wash.

In March 1963, RNMCB 18 assembled for the first time as an integral unit for training at Construction Battalion Center (CBC) Port Hueneme, Calif. Since then the battalion has held annual training consisting of military training, construction projects and individual training. Annual training has taken the battalion, whole or in part, from Japan to the Middle East and from Alaska to Belize. In 1990, over 30 Seabees from the RNMCB 18 were mobilized in support of Operations Desert Shield and Desert Storm in the Persian Gulf. In 1992, eight Seabees were recalled for Operation Restore Hope in Somalia

NMCB 18 was headquartered at Puget Sound Naval Air Station (NAS) at Sand Point in Seattle, Wash. in Building 27 until the spring of 1995. However, the NAS was being closed due to a Base Realignment and Closure (BRAC) decision. The battalion’s headquarters, along with several United States Marine Corps Reserve units, moved into a new $10 million building on Fort Lewis, Wash. in January 1995.

In 1991, RNMCB 18’s name was changed to Naval Mobile Construction Battalion (NMCB) 18, signifying the integration of the reserve units with the active units of the Naval Construction Force. Today, NMCB 18 reports to the First Naval Construction Regiment of the First Naval Construction Division. The battalion consists of 12 detachments scattered throughout the Pacific Northwest covering seven states:





Helena, Montana


Tacoma, Washington


Boise, Idaho


Everett, Washington


Spokane, Washington


Billings, Montana


Eugene, Oregon


Sacramento, California


San Jose, California


Reno, Nevada


Portland, Oregon


Anchorage, Alaska


In July 2006, NMCB 18 was mobilized to Gulfport, Miss. for three months of training in preparation for a 6-month deployment to Southwest Asia in support of Operation Iraqi Freedom and the Global War on Terrorism.

There have been numerous individual decorations and awards presented to the Seabees of NMCB 18, including five Seabees who gave their lives for their country. NMCB 18 has been awarded the Admiral John R. Perry Trophy for Best of Type three times. The battalion was the first reserve unit to be so honored in 1966 and the first battalion to win it a second time in 1970.  |  |  Navy FOIA  |  DoD Accessibility/Section 508  |  No Fear Act  |  Open Government  |  Plain Writing Act  |  Veterans Crisis Line  |  VA Vet Center  |  FVAP  |  DoD Safe Helpline  |  Navy SAPR  |  NCIS Tips  |  Privacy Policy  |  Site Map  |  Contact Webmaster
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