It's an island made mostly of silt. It's unstable and vulnerable to flooding. Seventeen years ago, it didn't even exist.

About 30 kilometres off the southern coast of Bangladesh, Thengar Char is a tiny island in the Bay of Bengal and Bangladesh officials are preparing it to house Rohingya Muslims fleeing persecution in neighbouring Myanmar.

Construction on the island has already begun, with streets being laid out, buildings being erected and flood barriers being made. But there are many unanswered questions about what the island will look like when it's finished.

David Yanofsky, a reporter with Quartz, has been examining satellite images of the island to get a better sense of what's happening there.

Satellite images of Thengar Char show the island in April 2011 (left) and May 2017 (right) (Quartz composite of DigitalGlobe and Planet data)

How many Rohingya will occupy the space?

According to the United Nations' refugee agency, more than 600,000 Rohingya have fled persecution in Myanmar into Bangladesh in the last six months.

Thengar Char is expected to house 100,000 of them and Yanofsky says there are concerns about over-crowding.

He says the entire area inside the flood barrier on the island is about 7.75 square kilometres and that the area where housing is being built will be about 1.5 square kilometres.

"Now if you just consider the [entire] area inside that barrier and you put 100,000 people inside of that, that is more dense than New York City," Yanofsky says.

"If you consider the area that's just flattened for buildings, putting 100,000 people into the 1.5 square kilometres, that's more dense than Manila or Mumbai."

People stand outside their shelters in the Kutupalong refugee camp in Cox’s Bazar, Bangladesh. (Allison Joyce/Getty Images))

How can it withstand weather events like monsoons and flooding?

The plan to develop the island is expected to cost a little over $350 million Cdn.

According to Reuters, the project will be undertaken by Bangladesh with help from British and Chinese contractors.

After the Bangladesh government approved the plan last November, Amnesty International's South Asia Director, Biraj Patnaik said that "it would be a terrible mistake to relocate the Rohingya refugees to an uninhabitable island," citing the risk of flooding as a key concern.

But Yanofsky says Bangladesh officials are confident they have the infrastructure to deal with the issue.

"Bangladesh has lots of experience building flood mitigation. Their country has a lot of low lying areas and obviously they deal with a lot of flooding every year," he says.

"The buildings that they're putting inside of this barrier are even built on stilts just in case these barriers could fail."

Thengar Char, where 100,000 displaced Rohingya are set to be relocated. (STR/AFP/Getty Images)

What will the living conditions be like?

Yanofsky says it is also not known how the Rohingya will be transported to Thengar Char, or what rights they'll have once they get there.

In February, an aid to Bangladesh Prime Minister Sheikh Hasina told Reuters that Rohingya staying on Thengar Char would only be allowed to leave the island in order to return to Myanmar or to accept asylum in another country.

Yanofsky says that while the Rohingya's living conditions on the island may be better than the refugee camps in Cox's Bazar, that's not the only issue.

"While this shelter that they're being provided may be better than living under [a] tarp or makeshift structures in the border region of Bangladesh and Myanmar, trading that for a complete lack of mobility off of an island...it's unclear how wise a decision that is and what type of humanitarian situation you create by isolating this group."

Rohingya Muslims carry their young children and belongings. New satellite imagery of Myanmar's Rakhine state shows the country's government is using bulldozers to flatten dozens of Rohingya Muslim villages that were burned during violence last year. (Bernat Armangue/Associated Press)

How are the Rohingya Muslims feeling about this plan?

Other reports suggest many of the displaced Rohingya have concerns about moving to the island.

But even so, Yanofsky says the Bangladesh government should consider building more development to house more refugees.

Human Rights Watch reports that the government of Myanmar has demolished dozens of Rohingya villages over the last three to four months, raising questions about what is left for displaced Rohingya to return to, even if they chose to.

"They [Bangladesh] need to find a place for all of these people because from all indications, they will not be allowed back into Myanmar," Yanofsky says.

"There is nothing left of the places where many of these people used to live."

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