A significant obstacle to the proposal was that current zoning at the site limits building heights to 400 feet (120 m).

Portland-based architectural firm William Kaven Architecture, helmed by brothers Daniel Kaven and Trevor William Lewis, proposed a twin-towered skyscraper complex to replace the to-be-demolished postal building, potentially including a new high-speed rail system hub.

[6] A significant obstacle to the proposal was that current zoning at the site limits building heights to just 400 feet, and the city council would have had to approve a major change to that element of the zoning for the proposal to be able to move forward.

[7][2] If built, the skyscrapers would have become the tallest buildings in Oregon, surpassing the Wells Fargo Center.

[5][2] However, Portland was not included in Amazon's shortlist of candidate cities for its planned second headquarters, announced in January 2018.