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Find: WWII Underwater Demolition Teams

Fold3 Image - Explanation of the work of Underwater Demolition Teams
Before there were the Navy SEALs, there were the Underwater Demolition Teams (UDTs) of World War II in the Pacific. UDTs were in charge of reconnaissance of the shoreline prior to an amphibious invasion. They would reconnoiter the lay of the beaches and offshore waters and be on the lookout for any natural or manmade obstructions that would hinder landing craft. They would then use explosives to demolish any obstacles.

Although the UDTs were preceded by the Navy Scouts and Raiders and the Naval Combat Demolition Units (NCDUs) in the European Theater, the need for a Pacific equivalent became obvious during the invasion at Tarawa in November 1943, when Marines became stranded on reefs that aerial reconnaissance had misjudged to be deep enough for landing craft. The Marines were forced to wade a thousand yards to shore, and some drowned and others were killed by enemy fire. This established the necessity of human surveillance of the shore waters before an invasion.

In the early days of the UDTs, members worked in the water in full fatigues and shoes, but real-world battle conditions showed the need for a greater emphasis on swimming, and UDT members began to wear swim trunks and fins, becoming the Navy’s elite combat swimmers. The 34 teams were involved in amphibious invasions across the Pacific, including in Saipan, Tinian, the Philippines, Iwo Jima, Guam, and Okinawa—just to name a few.

You can find thousands of mentions of UDTs on Fold3, especially in the WWII War Diaries. Below are examples of just a few of the types of information you can find about UDTs on Fold3:

Do you have any family members who served on an Underwater Demolition Team? Tell us about them! Or search for more info on UDTs on Fold3.


  1. Steve Rudge says:

    My father was the Commanding Officer of LCI(G)-472 and provided close-in fire in support of UDT activities at Guam and Okinawa. I am researching activities of the 472 and sharing with families of crew members. Any information that anyone has concerning these activities would be greatly appreciated.

  2. Kathy Remisiewicz says:

    My father, Eugene Remisiewicz was Gunner’s Mate Third Class in UDT 26 from 1944-1946. Originally from Detroit, Michigan, he did his primary Frogman training in Fort Pierce, Florida. Location of service: Great Lakes, Illinois; Patuxent River, Maryland; Fort Pierce, Florida; Maui, Hawaii; Guam (Mariana Islands); Yokosuka, Japan; China; Pacific Theater. He did an oral history for the Veterans History Project. Dad (still going strong at 90 years old) and I are working on a project to identify a series of photographs he has in a scrapbook. He has a brick in the walkway at the UDT/Seal museum in Fort Pierce.

  3. Richard Van Orman says:

    My wife’s uncle, Floyd William Spearin served with UDT #7, UCDU 122, “Higel’s Top Notch Terrors”. He was in several actions in the Pacific and was one of the first to set foot on Okinawa after the shelling, but before the invasion. His unique story is told in “The BLAST”, 2nd quarter 2005, Vol. 37, No.2. Journal of Naval Special Warfare.
    She wrote his unique story about this event.
    I believe his fellow team members identified so far were: Clyde V. Higel, Commander; J. P. “Pete” Peterson; Roy Gartrell; Herman Graff; B. F. “Andy” Anderson; T. L. Grass; Chief Richardson ; Pertison; C. E. Kroenke; W. O. Morrow.
    His story came full circle when she made contact in 2004, for him, with Okinawan’s who survived the invasion and returned their family photos he had found in 1945, on the beach.
    She will share any information with other UDT families.

    • Connie Eggers says:

      That was my father’s team, so any further information would be appreciated. He did at age 38, and even though he talked more about his experiences than many did, there’s still so much I’d like to know.

  4. Chuck James says:

    I think my dad was in a NCDU in the European theatre. He used to say that he was involved in every invasion before d day. I know that he was on the USS Ancon. How can I find out more about what he really did? He never told much about the war itself, only funny stories about shore leave and hints about actual combat. He enlisted in the navy in the summer of 41 and was in until the fall of 45. He died in 2003 and I would like to get more detail to share with his grandsons.

  5. Cheryl Lowry says:

    Does anyone know anything about UDT13? I believe that is the info I received from my father-in-law.

    • T. E. Romito says:

      MyUncle, Robert E Gleason,Ltjg, was with UDT-13,the were called The
      Black Cats. He was involved in recon and clearing beach obstacles for
      The IwoJima invasion.

  6. Betty Hichs says:

    My 3rd ggrandfather, Daniel Davidson, was one of the Virginia mountain men who fought in the battle of King’s Mountain. He then fought in the Revolution in 1777 in Col. Morgan’s Riflemen, CO. D. Also fought in Capt. Charles Porterfield!s Company of 11th Virginia Regiment. He was still serving in 1780.