The Portland City Council reversed itself Thursday, voting to advance a proposal for buildings up to 325 feet tall in the downtown waterfront district known as RiverPlace.

Towers built to that height would be as tall as the tallest buildings in the South Waterfront district. To reach it, however, the developer would have to earn a number of "bonuses" offered by the city in exchange for including affordable housing and other elements.

The development firm that owns the site has privately pushed an ambitious plan for towers that would include more than 2,000 apartments, and they circulated a concept by superstar architect Kengo Kuma that was first reported by Willamette Week.

Because any housing project would be subject to a 2017 city mandate that developers include rent-restricted units in any new housing, it would add hundreds of affordable apartments.

But that plan, while tempting in a city with a housing shortage, isn't a sure thing under the proposed zoning that also allows commercial uses, such as offices. To maintain some control over what goes on the site, the council also voted to require a master plan before any future development.

Commissioner Chole Eudaly had cast the deciding vote against increasing the height limits in February, joining Commissioner Amanda Fritz in voting no. She said she initially shared concerns about a proposal for tall buildings next to the river, which was discouraged under previous city plans, and for the eleventh-hour introduction of the issue.

The "no" vote drew considerable attention in part because Eudaly ran for her seat on a platform that centered on housing affordability, for which increasing the housing supply is key.

But she asked the council to reconsider on Thursday, this time joining with Mayor Ted Wheeler and Commissioner Nick Fish in voting yes. (Commissioner Dan Saltzman abstained because his family owns property in the district.) She said she was no longer swayed by the step-down policy.

"It was really intended to preserve the views of mostly commercial buildings," she said. "I have to say, I don't think our past policies of the past 30 years have resulted in a vibrant waterfront. It's a dead one."

Fritz, who voted against the taller height limits, said she was disappointed the council was "spot zoning" on a single site.

"This is against our adopted central city plan policy of step down to the river, which was discussed at huge length. It's abhorrent," Fritz said. "This benefits one property owner at the detriment of everyone else."

The owner of the affected property owner is NBP Capital, an investment firm led by siblings Lauren Noeker Robert and Spencer Noecker and backed by billionaire investor Nicolas Berggruen. It's been amassing property in RiverPlace over the last several years.

It acquired the RiverPlace Athletic Club in 2014, then evicted the operator of the gym in 2015 for failing to pay rent. It bought neighboring low- and mid-rise apartment complexes later that year, bringing its holdings to nearly 10 acres included in the redevelopment concept.

-- Elliot Njus

enjus@oregonian.com

503-294-5034

@enjus