A Portaferry Man in a Storm – Frank McNally on the Irish marine salvage specialist who helped save D-Day

In the weeks leading up to D-Day, 75 years ago, one of the operation’s crucial components was still lying on the bottom of the sea off southern England. It comprised a vast amount of concrete, formed into honeycombed caissons: the largest as big as a five-storey block of flats. These were to become the “Mulberry Harbours”, through which equipment and provisions for the invasion of Normandy would be landed.

After the Dieppe disaster of 1942, it was accepted by the Allies that capturing actual ports on that heavily defended coast was all but impossible. The invaders would instead have to construct temporary harbours, two of them, each the size of Dover.

To this end, the “Phoenix Caissons”, as they were known, had been sunk, or parked, on the English seabed in early 1944, awaiting their moment. When that came, their hollowed compartments would be pumped out and the blocks would rise – hence the “Phoenix” part of the name – before being towed across the channel. That was the theory, anyway. The practice proved much more problematic. And had it not been for the heroics of a now-forgotten salvage expert from Co Down, with the help of a well-timed accident involving one of the caissons, the operation might have been a disaster.

The salvage man's name was John Polland, originally MacPolin, and he was an odd candidate to become a saviour of the Royal Navy. The MacPolins were a staunchly nationalist family from Portaferry. A previous generation's naval experience had included internment on the HMS Argenta, in Belfast Lough, during the 1920s.That was the fate of John Polland's father, "lifted" in lieu of his brother Donal, who had been a member of a local IRA flying column.


By 1939, however, the younger Polland was a specialist in marine salvage, with 20 years’ experience. When the war came, this was enough to earn him a commission with the British admiralty’s salvage department. He had risen to captain by April 1944, in which capacity he found himself investigating a large concrete structure that had broken adrift while being towed and was now stranded on a beach near Littlehampton.

This in turn led him to discover the large number of similar “monstrosities” (as he put it) partly or wholly submerged along the coast. Such was the secrecy in which they had been constructed, neither he nor his immediate superiors had any idea what they were for.Indeed, the same secrecy explained the bad condition many blocks were in, inadequately finished or sunk carelessly by people who assumed them to be defensive structures that would never rise again.

It was not until a special meeting at the War Office on May 20th, when an envelope containing the navy’s orders for D-Day was opened, that Polland and others attending realised what the caissons were for. The date of the invasion remained a secret, however. So although Polland had acquired the task of raising the phoenixes, which he knew would not happen with anything like the alacrity expected, he did not yet know how urgent his task was.

The planners had envisaged caissons being towed to France at a rate of nine a day once the invasion began. But structural problems, including blocks that had cracked on being sunk, made for glacial progress. "Dear God," Polland wrote in his diary as pressure mounted, "how many more difficulties shall we discover before time runs out?"

Not until June 3rd would he learn that D-Day was set for the 5th (it was to be delayed a further 24 hours). By then, only four caissons had been raised. On the plus side, he now had orders from the top that anything required would be made available, including in one case a mile-and-a-half of six-inch steel piping to pump water.

Recalling Dunkirk, Polland also issued a late call for volunteers from every yacht or boat club on the south coast. The 24-hour delay was a big help too. This on June 5th, the admiralty was able to tell Winston Churchill that the required nine caissons would be ready to move on D-Day, with the same on D-Days plus 1 and 2. After that, there could be no guarantees.

In the event, Polland’s labours proved sufficient.  Although the harbour at Omaha beach was never completed before being badly damaged by a storm on June 19th, it remained useful in part. The one at Gold Beach, meanwhile, was a complete success.  It operated for months after D-Day, funnelling 2.5 million men, 500,000 vehicles, and four million tons of supplies into France. Some of the structure is still visible at the village of Arromanches-les-Bains today.