Is it true that the concrete floor in Key Colony Beach city hall sank several feet under the weight of the flood water?

» Mostly, no. Key Colony Beach city officials claimed the building was perfect before Irma. It wasn't. They "exaggerated" when they claimed that flood water had scoured out under the floor and that 4' of flood water had pushed the floor down into the chasm beneath. It didn't.
» In 2014 (three years before Irma), the City Engineer developed a repair program to repair the "sagging" floors in City Hall. City employees and visitors noted that the floors had been sagging for years.
» In 2019 the City Engineer examined City Hall again. He described the foundation system, walls, roof trusses, and soils. He found no structural concerns. He determined that "Hurricane Irma pushed hurricane force water into the structure for an approximate depth of 14". This salt water receded after 12 hours." (That amount of sea water loaded the concrete slab-on-grade floor about 73 pounds per square foot--not the hundreds of pounds claimed by city reports.)
» The City Engineer's 2019 letter also includes the plan the city accepted in 2014 (but never acted on) to stabilize the floor.
» Here's a copy of the report the City Engineer delivered on April 8, 2019.
» (And here's the "companion" question, Was the KCB City Hall ever actually condemned?)