All About Green

Reclamation - Apart from the ocean, what else will we lose?

Feb 2021
Author: Green Power
"Lantau Tomorrow" plans to reclaim the sea area
Artificial islands will be built on reclaimed land near Kau Yi Chau, Sunshine Island and Hei Ling Chau, under the Lantau Tomorrow Vision plan.

Lantau Tomorrow, or Lantau Tomorrow Vision to give its full name, is an ambitious plan announced in the 2018 Policy Address, to reclaim over a thousand hectares of sea for the long-term development of Lantau in the next few decades. We shall leave it to the experts when it comes to the deliberation of political and economic benefits of the proposal. As a green group, let’s dig deeper into the numerous environmental issues related to sea reclamation.

To begin with, where would the sand come from? In the early days, fill material used in Hong Kong came from mining hills. Later, sea sand from the seabed was exploited. In recent years, most sea sand used for fill is imported from mainland China and South East Asia. Mining of sea sand wreaks havoc on seabed ecology, and stirs up enormous amounts of suspended particles that make the waters murky, posing threats to marine organisms and their habitats. When the sand is dumped in a work site, the same problem repeats and causes second harm to the environment. Some mainland scholars have quantified environmental impacts of reclamation in Xiamen using the concept of “ecosystem services”. The study found that for every square metre of sea reclaimed, US$9.73 to US$14.72 of ecosystem services will be lost each year. Estimating from the scale of Lantau Tomorrow, we will suffer losses as high as US$140 million of ecological system services every year. The accumulating lose is astronomical.

Worse still, shortage of sea sand is bringing up the cost, endlessly raising the total budget. The government has suggested reusing local public fill materials (inert waste generated from construction and demolition works, such as mud, stones, concrete, etc.) for half of the demand. The other half will be replaced with the use of machine-generated sand. Does this make Lantau Tomorrow more “environmentally friendly”?

It is estimated that 260 million cubic metres, or 470 million tonnes, of fill materials are required for Lantau Tomorrow. According to information from the Civil Engineering and Development Department of Hong Kong, the existing capacity of the public fill bank is 23 million tonnes, accounting for a mere 5% of the total demand. In addition, at present more than 90% of the local fill materials are already reused. When local fill materials are used for Lantau Tomorrow, other local works will need to find alternative sources. It is a zero-sum game, and there is no extra benefit to the environment at all.

On the other hand, producing sand by pulverising large rocks with machines also consumes enormous amounts of energy and produces greenhouse gases. A research report by SINTEF estimated that 2.2 kg of carbon dioxide is generated for every tonne of sand produced with machines. To create 470 million tonnes of sand, 1 million tonnes of carbon dioxide will be discharged, equivalent to the annual carbon absorption of 46 million trees. This has not taken into account the whole production cycle of the sand such as mining and long-distance transport.

Facing criticism from the public, the authority often uses “environmental impact assessment” as a convenient shield. However, the Environmental Impact Assessment Ordinance of Hong Kong is out of date and lags behind world standards by almost 20 years. Important aspects such as impacts on climate and energy efficiency are not included. The government on one hand vows to achieve carbon neutrality by 2050; on the other hand, it largely neglects the climate impact of the reclamation project. The government has once again put its credibility in question.

We have so far discussed the single issue of “fill materials”. The reclamation works will also destrpy large areas of habitats of rare species including White-Bellied Sea Eagle (Haliaeetus leucogaster), sea pen and Bogadek's Burrowing Lizard (Dibamus bogadeki). The infrastructure will open up roads to South Lantau, bringing other development threats to land promised for conservation. Not to mention the large artificial island has to face the threats of climate change and sea level rise…

In the past, countless large-scale infracture projects have gone ahead without the promised economic benefits being realised. Today, when we have suffcient brownfields and idle land that can be used to solve the acute housing problem, and Hong Kong people’s collective wish for sustainable development, why do we still have to proceed with Lantau Tomorrow?