A Brief History of NMCB 18

Naval Mobile Construction Battalion 18 was formed during World War II on August 10, 1942 as the 18th Naval Construction Battalion at Camp Allen, Norfolk, VA. NMCB 18, a reserve unit in the 3rd Naval Construction Brigade, has had a lively history.

Soon after commissioning, the 18th NCB was assigned to Second Marine Division. At the request of the Marine Corps, the Seabees attached one NCB to each Marine Division. The 18th NCB maintained this relationship with the Second Marine Division for the remainder of the war. Accordingly, Charley Company and one-fourth of Headquarters Company were detached from the battalion on September 6, 1942 and reassigned to a replacement depot. The remainder of the unit was outfitted with Marine uniforms and equipment.

On September 19, 1942, the 18th NCB deployed to the South Pacific. After a long journey though Guantanamo Bay and the Panama Canal, the unit landed in Nomea, New Caledonia on November 11, 1942. The Seabees promptly went to work as stevedores and building facilities for the First Marine Amphibious Corps encampment. Bravo Company, reinforced, immediately moved forward to Henderson Field on Guadalcanal. The remainder of the battalion deployed to Guadalcanal on December 27, 1942. Assigned to build Fighter Strip No. 1 (Lunga Field) "with all possible haste," earth moving crews excavated some 60,000 cubic yards and filled in another 71,000 cubic yards to form the runway. Approximately 1.6 million square feet of steel Marston matting was laid on the runway surface. The airfield was placed into operation on February 9, 1943.

During this time, the 18th NCB was assigned to defend a sector of the beach. Nightly, Seabees manned a line of machine-gun emplacements. They also kept a main road and three bridges in good repair so responding combat forces could quickly deploy to attacking Japanese troops. Though never called to defend the beach during the Guadalcanal campaign, the Seabees of the 18th NCB were ready. The Japanese were not the only enemies encountered by these Seabees. Tropical diseases, including malaria, took their toll. By using strict preventative measures, the Medical Department reduced the malarial rate from new 16 cases per day to less than one.

After rest and relaxation with the Second Marine Division in Willington, New Zealand, the 18th NCB was redesigned as 3rd Battalion, 18th Marines on April 26, 1943. Five Seabee battalions were so designated in World War II. The battalion was coupled with two Marine engineering battalions to form a Marine Engineer Regiment. First Battalion was a Marine Engineer Combat Battalion; Second Battalion was a Marine Pioneer Battalion; and Third Battalion was a Naval Construction Battalion. Known as "Sergeant’s Battalions" due to the high number of petty officers, these units often landed in the waves behind the Marines and performed a multitude of engineering and shore party tasks.

Between November 21 and 26, 1943, a companyength detachment of 3/18th Marines deployed to Tarawa in support to the Second Marine Division. Tarawa is remembered as one of the most costly operations in Marine Corps history. Despite the lack of equipment and sniper fire, the Japanese airfield on Betio was ready for use 24 hours after work started. After two months on Tarawa, the detachment rejoined the remainder of the battalion at the Second Marine Division’s camp in Hawaii. In addition to training for coming operations, 3/18th Marines helped build the division’s camp. The battalion also ran the Public Works Department for the camp.

On April 1, 1944, 3/18th Marines was redesigned as the 18th NCB. Although now officially attached to the Fifth Marine Amphibious Corps, the 18th NCB was again assigned to the Second Marine Division for Saipan. Embarking in early May 1944, the battalion shipped out for the Saipan operation. Elements of the battalion landed in the first waves of Marines on June 15, 1944. Digging into the beaches, they worked around the clock getting supplies from barges into dumps. In addition, they rooted out and killed a number of the enemy, who had been passed over by the assault troops. When volunteers were called to take supplies to the front, details were soon filled by the men of the 18th NCB. In addition to working as a shore party, they accomplished considerable road construction and built a hospital. Very little equipment was available, and snipers, mortar attacks, and rain and mud were daily events. Several Seabees of the 18th NCB became casualties.

After Saipan was secured, eight Seabees volunteered to assist in the operation of a new LST ramp designed for the Tinian operation. This detachment landed on J-Day, July 24, 1944. The remainder of the 18th NCB followed on July 26, 1944, and set up camp. The unit’s primary project was construction of Camp Churo for some 11,000 displaced Japanese and Korean civilians. Built at the request of Second Marine Division G5 (Civil Affairs), construction included all housing, sanitation facilities, food and water supply and a security perimeter. A hospital for the civilians and camps for the garrison force was also built by the 18th NCB. For six months following their landing, the battalion encountered sniper fire and several attacks by Japanese troops hiding on the island. Five Seabees were killed and 38 received the Purple Heart for wounds during this period. Five Seabees were awarded the Navy and Marine Corps Medal for heroism.

The battalion remained on Tinian until decommissioned on June 20, 1945. The men of the 18th NCB had spent 32 long months overseas, one of the longest overseas tours of the war. 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. The 18th NCB was recommissioned 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, WA. The battalion’s headquarters, along with several United States Marine Corps Reserve units, moved into a new $10 million building on Fort Lewis, WA in January 1995.

In March 1963, RNMCB 18 assembled for the first time as an integral unit for training at CBC Port Hueneme, CA. 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; and in 1992, eight Seabees were recalled for Operation Restore Hope in Somalia.

In 1991, RNMCB 18’s name was changed to Naval Mobile Construction Battalion 18, signifying the integration of the reserve units with the active units of the Naval Construction Force. Today, NMCB 18 is attached to the First Naval Construction Regiment of the Third Naval Construction Brigade. The battalion consists of 14 detachments scattered throughout the Pacific Northwest covering eight states:

DETACHMENT	LOCATION
0118		Great Falls, Montana
0218		Tacoma, Washington
0318		Boise, ID
0418		Everett, Washington
0518		Spokane, Washington
0618		Billings, Montana
0718		Eugene, Oregon
0818		Sacramento, California
0918		Pocatello, Idaho
1118		Central Point, Oregon
1218		Reno, Nevada
1418		Portland, Oregon
1618		Anchorage, Alaska
1718		Missoula, Montana

There have been numerous individual decorations and awards presented to the Seabees of battalion, including five Seabees who gave their lives for their country. NMCB 18 had 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.