Water-based cities could help humanity adapt to a changing climate with a sustainable approach to development, a United Nations roundtable claimed Thursday. The event, which called for further investigation of the idea, also unveiled a concept vision for how these cities may look in the future.

“Floating cities are a means of ensuring climate resilience, as buildings can rise along with the sea,” UN Deputy Secretary-General Amina Mohammed said at a roundtable on floating cities in New York. “And when entire floating communities are designed from scratch, they can be designed as climate‑neutral from the onset. Why not use the abundant wind and water to cover all of their electricity needs?”

It may sound a bit like the Seasteading Institute, envisioned by Silicon Valley’s Peter Thiel as a libertarian paradise, but these habitats are less tech-fueled passion project and more a necessity as the global population shifts.

OCEANIX / BIG-Bjarke Ingels

The UN-Habitat team plans to partner with the Massachusetts Institute of Technology Center for Ocean Engineering, The Explorers Club, and floating cities non-profit group Oceanix.

OCEANIX / BIG-Bjarke Ingels

The group notes that two in five people live 100 kilometers from the coast and one in 10 live in a coastal area less than 10 meters above sea level. Erosion and flooding has the potential to affect millions.

OCEANIX / BIG-Bjarke Ingels

Bjarke Ingels, lead architect on the project, envisions a design where 10,000 people would live on the islands, with each 4.5-acre hexagon hosting around 300 people. Six platforms would make a village, and six villages make a city.

OCEANIX / BIG-Bjarke Ingels

Buildings would need to be between four and seven stories to ensure a stable structure, a key issue with a floating island.

OCEANIX / BIG-Bjarke Ingels

Ocean farms under the water would help the floating city achieve sustainability. Business Insider notes that an aquifer could help pull in water from the air.

OCEANIX / BIG-Bjarke Ingels

The goal is to develop a city with zero emissions, feeding off its own supplies and sustaining itself through ocean farming.

OCEANIX / BIG-Bjarke Ingels

Professor Joseph Stiglitz noted at the roundtable that the technology could have broad benefits: “Some of the most important benefits are not going to be in floating cities, but on land if you think about recycling waste and water.”

OCEANIX / BIG-Bjarke Ingels

Although deemed a floating city, the structures would be chained to the floor, around one mile from the shore. This would enable others to move them later if necessary.

OCEANIX / BIG-Bjarke Ingels

“All of the aspects of human life would be accommodated,” Ingels told ArchPaper. Ingels envisions seven more islands that would offer recreation, spiritual and cultural facilities. “It won’t be like Waterworld. It’s another form of human habitat that can grow with its success.”

OCEANIX / BIG-Bjarke Ingels

The idea could be needed now more than ever. Maimunah Mohd Sharif, executive director of UN-Habitat, told Reuters that “floating cities is one of the possible solutions” to increasingly-crowded cities pushed by climate change.

OCEANIX / BIG-Bjarke Ingels

“Nine out of 10 of the worlds largest cities will be exposed to rising seas by 2050,” Ingels said in a statement. “The sea is our fate — it may also be our future.”

OCEANIX / BIG-Bjarke Ingels

With 2018 ranking as the fourth-hottest year on Earth ever, it’s the sort of radical change that could be needed urgently.