The island no longer exists as it did. Its flooding was not an accident of weather but a deliberate consequence of one of the most ambitious engineering projects in the early Irish state, and the burial ground and church that stood there were dismantled, excavated, and relocated before the waters came.

In the late 1920s, the Electricity Supply Board began harnessing the Shannon at Ardnacrusha in County Clare to generate hydroelectric power, a scheme that required raising water levels along a significant stretch of the river. Friar's Island, which sat in the Shannon in what is now the Killaloe area, would be submerged. Before that happened, excavations were carried out and the church was taken apart stone by stone and re-erected in 1929 in the grounds of the Roman Catholic church at Killaloe. The building, as reassembly work revealed, was a nave and chancel structure, the nave being the earlier element with the chancel added at a later date. What the excavations also uncovered, prior to the move, was considerably more complex than a simple island chapel. The church had been built on a raised stone platform, enclosed by what may have been a cashel, the term for a stone-walled enclosure typically surrounding an early ecclesiastical or secular site. A second stone platform, roughly 6.7 metres north to south and 15.25 metres east to west, lay to the south of the church. Most strikingly, eleven skeletons were found beneath or close to the foundations of the church's north wall. The excavations were published by R.A.S. Macalister in 1929, who documented the platforms, the possible revetment wall of uncertain function, and the human remains.

The reassembled church can still be seen in the grounds at Killaloe, its stones carrying the history of a site that no longer has a physical location above the waterline. The burials and the platforms they overlay remain known only through that 1929 excavation, their original island context now permanently altered.