World War II Navy Frogmen Training at Fort Pierce

Fort Pierce earned the name because the Navy moved its Naval Combat Demolition Unit training there on June 6, 1943, and those units grew into the Frogmen and later the Navy SEALs.

The World War II history kept by Naval Special Warfare Command says the Chief of Naval Operations ordered the establishment of Naval Demolition Units with a permanent training program in January 1943, that training began at the Amphibious Training Base in Solomons, Maryland, and that it was moved to Ft. Pierce on June 6, 1943 (Naval Special Warfare Command WWII history). The units started with many volunteer Seabees and men from other branches, who trained alongside the Amphibious Scouts and Raiders; the command dates the Scouts and Raiders school at Ft. Pierce to four months after the November 1942 North Africa landings.

Florida's park managers use the same language for the Fort Pierce Inlet shore. The state's 2021 management plan for Fort Pierce Inlet State Park names the park and the water beside it as the place where the Navy Frogmen were born and trained during World War II, and says thousands of them trained on the inlet grounds (DEP Fort Pierce Inlet State Park plan). The City of Fort Pierce also calls the city the birthplace of the Navy Frogman on its page for the National Navy UDT-SEAL Museum (City of Fort Pierce UDT/SEAL Museum page).

The U.S. Army Corps of Engineers describes the wartime base as a 19,280.48 acre site running about 25 miles along the Treasure Coast, including North and South Hutchinson Islands.

On its Formerly Used Defense Sites page, the Corps' Jacksonville District says the Fort Pierce Naval Amphibious Training Base extended from near Vero Beach to near Jensen Beach, that the military acquired it during World War II for a Navy training facility, and that the Navy built more than 450 buildings plus roads and water and sewer systems (USACE Fort Pierce Naval Amphibious Training Base page). By January 1943, detachments of Scouts and Raiders had begun arriving.

An older Corps report draws the edges a little differently. The December 2012 Revised Inventory Project Report places the property in Martin, St. Lucie and Indian River counties, from near Jensen Beach to approximately five miles south of Vero Beach, built on the beaches of North and South Hutchinson Island and the causeway linking Ft. Pierce to South Hutchinson Island. It says the land holdings, mostly leased, totaled almost 20,000 acres, as many as 10,000 of them submerged, and that up to 40,000 personnel were trained at the installation, many housed in temporary semi-tent structures called hutments (USACE Revised Inventory Project Report, 2012). The two Corps documents therefore place the northern end of the base differently, near Vero Beach in one and about five miles south of it in the other.

The Fort Pierce units trained to blow up beach and underwater obstacles ahead of amphibious landings, working in six man teams of one officer and five sailors.

Naval Special Warfare Command says the Naval Combat Demolition Units specialized in explosives and underwater obstacles for amphibious operations, that the intensive Hell Week program begun in May to June 1943 evolved into the present day Basic Underwater Demolition/SEAL (BUD/S) training classes, and that the first NCDU class graduated in September 1943 (NSW WWII history). The 2012 Corps report lists what the Fort Pierce installation held for that work: submerged obstacle training areas, mine removal training areas, beach landing sites and anti-aircraft gunnery training areas, all part of a training site for the invasion of Europe (USACE 2012 report).

A second mission joined the first in 1943. The Corps says amphibious training at the base used high explosive rockets, bombs, antiaircraft guns and small arms, and that the Joint Army-Navy Experimental and Testing Board was set up that year to develop and test ways of breaching and removing the beach fortifications expected in Europe and Japan. Beaches along the northern portion of the base were fortified so that a variety of ordnance could be tested against them (USACE Fort Pierce base page). The Fort Pierce Inlet State Park plan says Dynamite Point, at the western end of the Fort Pierce Inlet, got its name from the Navy Underwater Demolition Team training there in exploding ammunition (DEP Fort Pierce Inlet State Park plan).

On D-Day, Naval Special Warfare Command says, 34 Naval Combat Demolition Units joined U.S. Army Engineers in combined teams to clear obstacles at Omaha and Utah beaches in Normandy; NCDU training had moved to Fort Pierce the year before.

For the Normandy NCDUs, whose training program had moved to Fort Pierce in 1943, the command's history records that 37 NCDU men were killed and 71 wounded, the heaviest casualties in Naval Special Warfare history, that the NCDUs at Omaha Beach received the Presidential Unit Citation, and that those at Utah Beach received the Navy Unit Commendation (NSW WWII history). In the Pacific, the same history says, 34 Underwater Demolition Teams were established and saw action in every major amphibious landing.

The Normandy link is written into a Treasure Coast place name. The Florida Department of Environmental Protection's 2014 plan for Avalon State Park on North Hutchinson Island traces the name to the Navy men who trained on that shore in World War II before the Normandy invasion, and says the Navy used the park area to sharpen its landing craft crews and to develop the Frogmen, later the Navy SEALs (DEP Avalon State Park plan).

The clearest traces are the submerged wartime obstacles off Avalon State Park and the Dynamite Point and inlet grounds of Fort Pierce Inlet State Park, both on North Hutchinson Island.

The Avalon plan dates the submerged hazards along part of the park's ocean shoreline to that wartime training (DEP Avalon State Park plan), and the Florida State Parks page for Avalon tells swimmers and snorkelers to watch for underwater obstacles from World War II amphibious exercises (Florida State Parks, Avalon State Park). The same 2014 plan listed a ranger-led history walk, then offered on request, about Avalon State Park as a U.S. Navy SEAL training location. The Fort Pierce Inlet State Park plan says that park still protects the places that mattered to the war effort (DEP Fort Pierce Inlet State Park plan); the Fort Pierce Inlet State Park guide covers the park itself.

Most of the Fort Pierce base is gone. The 2012 Corps report says most facilities were removed when the installation closed in 1946 and the property was returned to its owners (USACE 2012 report), and the Corps' base page adds that much of the former base area has since been developed with residential, commercial, governmental and educational facilities (USACE base page).

The Corps is running a Remedial Investigation and Feasibility Study to learn whether anything from the wartime training remains on North Hutchinson Island and offshore, and in what amounts and locations.

For the former Fort Pierce base, the February 2017 fact sheet says a Site Inspection was completed in 2015 and found that three project areas need the study, and it records where munitions have turned up since the war (USACE Remedial Investigation fact sheet, February 2017). The Corps' current base page says field teams are in the second phase of work, digging up metallic objects located earlier by digital metal detection to identify them (USACE base page).

For anyone on a Treasure Coast beach or building site who finds a suspicious object, the Corps' Fort Pierce page gives its 3Rs: Recognize that the object could be dangerous, Retreat without touching or moving it, and Report it by calling 911. The page lists the Jacksonville District's toll free Formerly Used Defense Sites line, 1-800-710-5184 (USACE base page).

Last verified: October 22, 2026, for the Fort Pierce Frogmen history, checked against the Naval Special Warfare Command WWII timeline, the USACE Fort Pierce base page, its 2017 fact sheet and 2012 inventory report, the DEP plans for Fort Pierce Inlet and Avalon state parks, the Florida State Parks Avalon page and the City of Fort Pierce museum page.