Don Allerston gives an account of clearing the graves to make way for the new dock.
“In 1957 work started at St. Mary’s Birkenhead, by the firm of J. Doyle Demolition of Liverpool. Its contract was to move all the dead from St. Mary’s graveyard, Birkenhead and re-inter them at Landican Cemetery, near Arrowe Park. Notices were put in local papers of the fact, and anyone who had relatives buried there and wanted to make alternative arrangements were asked to contact the company, on site.
Work began in 1957 and was to finish in 1958. The removal and re-burial was carried out by 58 local men, men from Birkenhead and Liverpool. They ended up moving 5,500 bodies.
When work started each gravestone was marked with a number, the stones were then removed and a wooden stake was knocked into the same location, and the same number was put on the stake. A ramp was started about 30 feet away, which sloped down from ground level to a depth of six feet, thereby allowing the men to dig into a six foot high (grave) wall.
Next the last one to be buried (on top) was the first to be removed. It was put in a carry-off box and taken to the site mortuary, where it was put into a new coffin and its location number was put on. It was then ready for transportation to Landican cemetery where its previously marked gravestone was waiting.
On the other side of Cammell Laird’s a dyke had been built out from the shore, then it continued at right angles, then back to the shore. The site waste from St.Mary’s was then used to infill this inverted U-shape, so reclaiming the land back from the river.

The photograph shows the gravestone with its marker number still readable nearly 50 years later.

The first photograph shows the new dock under construction, and the bottom picture shows the dock as it appears now. Both pictures show the wall of St.Mary's marking the boundry of the old graveyard.

The old graveyard of St.Mary's

W. F. Bushell, 'The Ancient Graveyard of Birkenhead Priory', T.H.S.L.C. cviii. 141 is the best source of information about the old graveyard before it's demolition to make way for the new Dock at Lairds.

The modern church of St. Mary was built within it about 1820 at the expense of the lay owner, who no doubt saw the expansion that was coming, but the greater part of the churchyard was untouched. Of recent years friends of the Priory have urged that it should be made into a small park, and that, if the ecclesiastical authorities were unable or unwilling to maintain it, they should offer it free for that purpose to the Town Council. Many members of the latter,and others, had expressed themselves as favourable to the suggestion, but unfortunately nothing was done in spite of the efforts of the few. Such an open space, where there are so many inhabited buildings crowded together, would have been of great value to the community, and it caused keen regret when it was heard that the ecclesiastical authorities were proposing to sell it in order that a new dock could be constructed on that site. Thus were shattered for ever the hopes of those who had envisaged the provision of a small park in which old people and others could see visions and dream dreams of the past. Indeed some had looked forward to a day when buildings to the east of the site could be remoV6d," revealing once more a view of the Mersey on which, from this headland of birch trees, the monks had gazed for four centuries, followed, for a further three centuries, by the lay owners and their friends. It has already been stated that many had regretted the state of desolation into which the graveyard had been allowed to fall, and had long urged that it should be handed over to the Town Council for the above purpose. The precedent of 1896 would then have been followed when the Council secured the majority of the ruins, and gladly spent £3,000 on their restoration and repair. Much of this was done under the influence and supervision of the Historic Society or Lancashire and Cheshire. It was for this reason that this new threat naturally alarmed the Society, so that they sent representatives' to the government enquiry held at the Town Hall, Birkenhead in the earlier part of 1956. Some of their members had been active for months beforehand, with letters to the Press, and interviews with those concerned. Unfortunately, however, the Society was helpless against the combined opposition of industrialists, Town Council, and, most unhappily, the ecclesiastiical authorities, who had little regard for their ancient inheritance. Thus there will pass away the holiest spot in Birkenhead, where rest the bodies of the holy men of the past who served God in prayer and praise upon this headland, and where also rest the bodies of our predecessors who, after the dissolution, played their part in the life of Wirral and served their generation. One more thing should be said. Our Society has always recognised the needs of the present generation, and has never neglected that aspect. In this small island some fifty million people live. They have to export to live. Industries have to be encouraged and helped, and the use of this graveyard may be essential to the continuance of our present standard of life. The Historic Society, while it deplores the loss of the graveyard, realises such needs full well; but it is justified in deeply regretting such a loss, however necessary it may be.

St. Mary's Church, Birkenhead

“When the first extensive changes of property were made in Birkenhead in1817, mr Price engaged with Messrs. Hetherington and Grindrod of Liverpool, that he would erect a Church, at his own expense, on the elevated ground immediately adjacent to the ruins of the ancient Priory, which were then surrounded with fields, having only a footpath from the old Chapel to the Chester Road. Accordingly on the 19th July 1819, the foundation stone of a Church, dedicated to St.Mary, was laid with much ceremony by the Right Hon. Lord Kenyon.

The building, in the first instance, comprehended only a body and chancel, with a north and south porch, having also a tower and spire: but the increased population of the township having rendered further accommodation requisite, two transepts, each 42 feet by 36, have subsequently been added. These are evidently not the production of the eminent architect and antiquary, Thomas Rickman, by whom the original designs for the Church – the first to be built – were furnished.

Externally the Church is principally distinguished by an elegant tower and spire, together about 130 feet in height: the latter is a very conspicuous object from every part of the surrounding neighbourhood. The tower contains a peal of six fine-toned bells, and is furnished with a clock, placed much too low for general utility. The Churchyard is extensive, and includes the ancient burial ground of the Priory in which are several tombs of an old date, but there are no monuments of interest in either. An old gravestone discovered in 1818, and which from the description appears to have covered the remains of one of the ancient priors, Thomas Rayneford, has been worked into the wall near the door of the old Chapter House, wherein nearly five centuries since. He presided over the Councils of the Priory.

The church has latterly become, by purchase, the property of William Jackson, Esq. Whose name is so intimately connected with Birkenhead. The Rev. Andrew Knox is, and for the last seventeen years has been the Incumbent.”

(The history of the Hundred of Wirral by William Williams Mortimer first published in 1847 by Whittaker & Co., London)