If a proposal to bring tall apartment towers to the waterfront comes to fruition, an internationally renowned architect might have a hand in shaping Portland's new skyline.

Japanese architect Kengo Kuma, who designed the Portland Japanese Garden's new buildings and Tokyo's 2020 Olympic Games stadium, is working on the designs to build skyscrapers at RiverPlace.

WW first reported this morning that the project's developer is offering to build as many as 500 affordable apartments, in exchange for the city allowing the buildings to rise as high as 400 feet tall. The new neighborhood would step down from Portland State University to the Riverplace Marina and Tom McCall Waterfront Park.

Kuma's firm is the second architect listed on project documents. The other is locally based GBD Architects.

WW has obtained the early designs, which are being circulated in City Hall. Four city commissioners have expressed interest in the project—which needs their votes to change the height limits near RiverPlace. (The latest plans only allow developers to erect 200-foot buildings.)

Here's a look at the preliminary imaginings of what the apartment towers could look like if City Council lets Kuma go tall.