Developers Riverside Investment & Development and Howard Hughes Corp. are planning to build a 51-story skyscraper at 110 N. Wacker Drive, according to the Chicago Tribune. The site by the Chicago River is occupied by the General Growth building. Because the building could be considered an architecturally significant building, the U.S. Army Corps of Engineers has stated the development could have an “adverse effect." 

The developers were planning to begin construction on the skyscraper as early as January, but the timeline will likely have to change.

The five-story General Growth building, an example of mid-century modern architecture, is eligible for inclusion on the National Register of Historic Places according to the report. That means the federal agency’s Chicago District will be accepting public input before deciding whether or not the developers can move forward with demolishing the building.

The development already received city approval but now the input from the U.S. Army Corps of Engineers has created a hitch in the developers’ plan.

“We have been working through the permitting process with the U.S. Army Corps of Engineers and other statutory authorities and look forward to working collaboratively to deliver this exciting new building in the heart of Chicago,” said the developers in an emailed statement, according to the report. 

The Chicago Tribune noted that is unsure how likely it is the U.S. Army Corps of Engineers review will derail development.