The Fordham Spire would measure 1,458 feet to its roof, reaching about 2,000 feet to the top of its spire. That would make it the tallest structure in the US, surpassing the current holder of that title, the Sears Tower, also in Chicago, as well as the proposed Freedom Tower, which is to be built on the site of the World Trade Centre in New York.
Aside from the height, however, the project is likely to inspire passions not least because it has been drawn by Mr Calatrava, an engineer and architect whose recent rapid rise to international prominence has caused some to dub him the new "starchitect".
The first blueprints show a building that is surprisingly slim - better to counter Chicago's fierce winds. It would taper towards the top and be distinguished by twisting grooves that make it look much like a drill bit or a birthday cake candle.
The man who hired Mr Calatrava is a local developer named Christopher Carley, whose company is the Fordham Company, hence the tower's name. It would be contain luxury apartments and 20 floors of hotel accommodation.
Less than delighted at the plans is the developer Donald Trump, who scaled down his ambitions for a residential tower in Chicago after the 9/11 terror attacks. Now under construction, his building will reach 90 storeys, compared with 115 for the Calatrava-designed tower. "I don't think this a real project," Mr Trump said, with a warning about the temptation it might present to terrorists. "It's a total charade."
The fate of the proposal is likely to rest on economic factors and investors still need to be found to finance its construction.
But even before that, any political obstacles must be overcome. So far, the reactions from the local politicians seem promising.
"It's going to put Chicago on the map," Burton Natarus, an alderman for the area on the shore of Lake Michigan where the proposed tower will stand, said. "I'm not concerned about height. And I'm not concerned about density, because it's a sliver. It's like a needlepoint."Reuse content