I have no problems with some sort of settlement in shallow water. The last glaciation took sea level down 100 m or so, andthere were seaside fishing village then. Some have been the site of underwater archaeology.

In this case, as with reports of a sunken city offshore Japan, more likely these are angular rocks, forming a grid pattern reminiscent of city layouts. My profession involves imaging the seabed and I can assure you we see a whole range of things that would excite your average UFO watcher, but have perfectly natural geologic explanations.

2200 ft (670 m) is hellish deep and either implies an age that is not credible, or a subsidence rate that is incredible. Worldwide, we see those depths on foundered shelves that are 5 million years old, but there were no humans then, and - of course - the process of sedimentation and erosion would almost totally destroy any city in that time, even its foundations...

If they're right, it's the discovery of the millennium. Unfortunately, they're more likely wrong...

Note this is all dated 2001, so not current...