Hong Kong (CNN)Hong Kong plans to build one of the world's largest artificial islands, at a cost of around $80 billion.
However, the Lantau Tomorrow Vision project has come under fire from a number of quarters over environmental concerns and the massive cost to the city's coffers.
Revealing the proposed budget Tuesday -- an amount roughly half the city's current fiscal reserves -- Secretary for Development Michael Wong said the project was necessary due to Hong Kong's "serious shortage of land supply."
To this end, Wong said, around 1,000 hectares of land would be reclaimed near Lantau, the largest island in Hong Kong and home to the city's airport. This could be used to build up to 260,000 residential units, of which 70% would be reserved for public housing.
By comparison, Dubai's Palm Jumeirah island, also created by land reclamation, measures around 560 hectares.
Hong Kong is one of the most densely populated places on earth, and housing prices have long surpassed affordability for most of the city's residents. Large amounts of land held in reserve by property developers, demand for housing by mainland Chinese investors, and relatively low amounts of public housing versus private rental accommodation has exacerbated the issue.
In a statement, Greenpeace Hong Kong criticized the government's Lantau plan for overlooking what it said were cheaper and less environmentally detrimental solutions to land shortage, including the development of brownfield sites, land formerly used for industrial sites.
"Compared with reclamation, (development of) brownfield sites has high public support and the cost is cheaper," said Greenpeace campaigner Andy Chu.
According to the World Wildlife Fund, there is currently 1,200 hectares of brownfield site that could be developed for public housing, greater than the amount of land to be created by the Lantau project.
Save Lantau, a pressure group, has accused the government, led by Chief Executive Carrie Lam, of ignoring public opinion on this issue and pressing ahead with reclamation at the expense of alternative solutions.
Pointing to associated costs such as transport and other infrastructure development, the group estimated the total cost could run upwards of double the government's proposed budget.
"(This) will be the most expensive, complex and riskiest infrastructure project in Hong Kong's history," the group said in a statement on a previously announced draft of the plan, urging Lam to "immediately withdraw" the plan.
According to Wong, the development secretary, the costs of the Lantau project will be recouped by revenue the government will receive from selling the reclaimed land to developers.
While part of the plan will involve a $127 million conservation fund, environmental groups have raised serious concerns over the potential effects of the huge reclamation project on local species, particularly the endangered pink dolphin.
Previous projects -- such as the development of Hong Kong International Airport and a colossal bridge linking Hong Kong to Macau and mainland China -- have included the creation of protected areas for the dolphins.
However, these have come in for criticism on timing and practicality. One sanctuary created for the airport project was not officially designated until reclamation was well underway, and depended on the dolphins finding their way past that and initial work on the bridge to an area outside of their usual habitat.
There are also concerns over the future proofing of reclamation projects as global sea levels are rising due to climate change. According to the South China Morning Post, Wong said the new island would sit at least six meters (19 feet) above current sea levels, the same as the city's airport, and would be designed to withstand the type of super typhoons experts say the city will face more off as temperatures and sea level rises.