Back in November, we brought you news about 4/C, a 102-storey tower proposed for Fourth Avenue and Columbia Street in Downtown Seattle. At a height of 339 metres, or 1,111 feet, the project is now running into some opposition from the Federal Aviation Administration (FAA). 

4/C, image via Crescent Heights

Miami-based Crescent Heights received a "notice of presumed hazard" from the FAA, who  has deemed that the proposal interferes with navigable air space following an initial review of the application. Most notably, the project could impact travel to and from Boeing Field, an airport situated five miles south of the downtown core. The FAA has also raised concerns that the tower and its crane could have adverse effects on helicopters using the nearby Harborview Medical Center. 

4/C, image via Crescent Heights

The FAA stated it would approve a 302-metre, 992-foot revised proposal — measured from the ground level on the building's western corner along Columbia Street between 3rd and 4th Avenues — which would still make it the tallest building in the city. Each corner is assessed individually by the FAA and more significant restrictions have been placed on the rest of the site, the shortest of which is a 965-foot limit at 4th Avenue and Cherry Street. The current tallest building, Columbia Center, was also slapped with a height decrease from the FAA when it was originally proposed. 

Columbia Center, image retrieved from Google Street View

The plan calls for a mixed-use tower designed by LMN Architects composed of 1,200 residential units, 150 hotel rooms, and 167,500 square feet of commercial space. The FAA applies their review process to nearly all tall building proposals. If Crescent Heights gets the go-ahead from the FAA, 4/C would still need to traverse Seattle's planning process and obtain approval before a building permit can be issued. 

4/C, image via Crescent Heights

Even if some height is chopped off 4/C, Seattle still has a number of impressive towers coming through the pipeline. An 888-foot tower at 888 2nd Avenue by Urban Visions and NBBJ would become the third tallest building in the city. NBBJ has also designed the 58-storey Rainier Square Tower, a Wright Runstad & Company-developed skyscraper with a sleek curved wall that will contain residential and office uses. A smaller 12-storey building will host a 155-room hotel. You can check out these and other major projects reshaping the city here or by visiting Seattle's dedicated Forum section

888 2nd Avenue, image via Urban Visions

We'll keep you updated as 4/C makes its way through the approvals process. In the meantime, you can visit the Database file linked below for more images and information, head over to the project thread, or leave a comment below to get involved in the discussion.