$40bn Giant Sea Wall will not save Jakarta from sinking, water experts say
A massive sea wall being constructed near Jakarta to keep out the encroaching ocean is angering fishermen, who fear for their livelihoods, and is also being criticised by water experts, who say it does not do enough to tackle land subsidence.
The city’s northern areas have sunk by four metres in the past 40 years, Japanese experts say, while some ‘hot spots’ are said to be dropping as much as 20 centimetres a year.
The 10 million residents of the low-lying coastal city, built on a swampy plain, are exposed to tidal and seasonal flooding. In 2013, parts were submerged under nearly two metres of water after a heavy monsoon storm.
Jakarta’s vulnerability to floods - already exacerbated by population growth, urbanisation and changing land use - rises with every centimetre the ground falls.
Experts and residents agree that over-extraction of groundwater for drinking and commercial use is largely responsible for the land subsidence. What they don’t agree on is how to tackle the problem. An iconic infrastructure project intended to ease Jakarta’s flooding woes is currently mired in uncertainty.
The Dutch - regarded as the foremost authorities on the concept of “living with water” - are lending their expertise via the flood prevention plan, involving a giant sea wall that will close off Jakarta Bay and which could cost up to $40bn.
However, critics say that the National Capital Integrated Coastal Development (NCICD) programme does not address land subsidence, the underlying reason for flooding.
At the same time, “the government is throwing away access to the sea” for tens of thousands of people in the bay who rely on fishing and fish-processing, said Ahmad Marthin Hadiwinata of the Indonesia Traditional Fisherfolk Union.
He worries that local residents will be evicted from their homes to make way for the new infrastructure.
Unveiled in 2014, the project - colloquially known as the “Great Garuda” or “Giant Sea Wall” - involves raising and strengthening the existing onshore embankment of Jakarta Bay, as well as constructing a 24km outer sea wall and developing real estate on artificial islands reclaimed from the ocean.
Seen from the air, the mega construction project was initially shaped like a garuda, the bird-god of Hindu mythology that is Indonesia’s national symbol.
The design was changed in response to opposition and a government request to incorporate another project led by private developers to build 17 artificial islands, said Victor Coenen, Indonesia representative for Witteveen+Bos, a Dutch engineering consultancy leading the NCICD consortium.
Its partners, which also include South Korea, are now awaiting the government’s decision on the final plan, he added.
A June document outlining an updated NCICD master plan confirmed the new design and emphasised the importance of stopping land subsidence, as well as addressing water and sanitation issues.
The Ministry of National Development Planning did not respond to requests for comment.