“Gigantic,” “Over-the-top” and “Controversial” are just three of the adjectives used thus far to describe 500 Alton, a new, 50-story residential tower that may one day hover above the entrance to Miami Beach.

“Ambitious” might be added to the list as well.

Sleekly designed by Perkins+Will, with a thoughtful and sustainable landscape design from Urban Robot, the project represents a big and complex idea that’s being floated by Crescent Heights developer Russell Galbut. It’s proposed for a site covering three city blocks, already surrounded by towers, some 20 stories tall.

“It’s been owned by the developers’ family for some time,” says Jose Gelabert-Navia, managing principal at Perkins+Will. “It’s the largest single property left in Miami Beach that’s privately held.”

By right, the structure could be eight stories tall and occupy the entire site. That would mean about 300 condominiums, most without views. A taller, thinner structure on the southwest corner could mean just 80 condominiums – four on each floor, plus a penthouse – and all with views.

It also would mean a 3.25-acre park. “He will give the city a public park, with a $20 million value on the land,” he says. “He will give it, build it and maintain it.”

It’s a tradeoff that’s already generating discussion – and not just about height. There’s talk also about how to manage stormwater in an area that some say will be three feet underwater in just 20 years. Part of the city’s solution for that is a series of pumping stations.

Justine Velez, partner in Urban Robot, wants to use landscape planning to augment those pumps on site – with cisterns, lakes and a stream. She wants to filter and clean rainwater before it’s returned to Biscayne Bay. And she wants to offer the public a state-of-the art area for recreation.

“The pumping stations are great, but we can add more stormwater storage, improve the quality of water and provide these recreational opportunities,” she says.

There’s time for talk about that before the mayor and city commission of Miami Beach make their decision late this year. Indeed, city attorney Jose Smith has issued an opinion that a public referendum may be called for, depending on whether the site is considered a single parcel or multiple ones.

Whether it gets built or not, 500 Alton has already achieved a significant milestone:

It’s elevating discourse about the role of landscape architecture in urban, East Coast stormwater management.

Tomorrow: More on Urban Robot’s Proposal

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