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In flood-prone Jakarta, will 'giant sea wall' plan sink or swim?
Reuters - September 14, 2017
The city's northern areas have sunk 4 meters in the past 40 years, Japanese experts say, while some "hot spots" are said to be dropping as much as 20 centimeters 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 meters of water after a heavy monsoon storm.
Jakarta's vulnerability to floods – already exacerbated by population growth, urbanization and changing land use – rises with every centimeter 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 it. An iconic infrastructure project that is supposed to ease Jakarta's flooding woes is 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, which could cost up to $40 billion.
Critics, however, say the National Capital Integrated Coastal Development (NCICD) program 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 – and better known as the "Great Garuda" or "Giant Sea Wall" – the project involves raising and strengthening the existing onshore embankment of Jakarta Bay, as well as constructing a 15-mile 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.
But 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, seen by the Thomson Reuters Foundation, confirmed the new design and emphasized 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.
Fishermen suffer
The NCICD is one of many water projects the Dutch have embarked on in their former colony. In May, Indonesia gave the go ahead to Dutch companies to build the world's largest tidal power plant in eastern Indonesia.
Three Dutch non-profit groups – Both ENDS, the Centre for Research on Multinational Corporations (SOMO) and the Transnational Institute – said in an April report that the NCICD threatened the livelihoods of tens of thousands of people and had failed to follow design guidelines that would apply in the Netherlands, calling it a "pseudo-solution."
Hadiwinata from the Fisherfolk Union said local communities also object to a lack of consultation and impact assessments.
At least 25,000 fishermen have been hit by work already done for the project and other land reclamation initiatives along Jakarta Bay, which have caused sedimentation, he added.
They have to go further to find fish, whose numbers are now very low, he told the Thomson Reuters Foundation.
Many, including Hadiwinata, are hoping Anies Baswedan, who won a hard-fought election for the post of Jakarta governor in April, will stop or modify the project when he takes office in October. Work was suspended for several months in 2016 amid regulatory and environmental concerns.
During his campaign, Baswedan was vocal about his opposition to the NCICD but has said nothing since. He was not available to comment for this article.
Coenen said stopping land subsidence is important but could take 15 to 20 years, meaning Jakarta should work on flood prevention at the same time. The future of the crowded city's flood protection lies offshore because it has no space for flood basins, he added.
"It's only a question of how far offshore you go, how big you want to build, and how long you want it to last, because the smaller the scheme, the shorter the lifetime will be," he said.
The project's first phase of strengthening the existing embankment along Jakarta's shoreline, which began in 2014, is about a third complete, Coenen said.
Learning from Tokyo
Critics of the NCICD are hoping a three-year project to study and stop land subsidence, agreed in July between Indonesia and Japan's international development agency JICA, could help.
It involves developing better monitoring systems to measure where subsidence is worst and groundwater extraction heaviest, raising awareness of the dangers, and undertaking mitigation measures such as regulating groundwater usage.
It may be one to two years before there is reliable, consolidated data on land subsidence, but the findings will feed into the NCICD, JICA said.
"Tokyo started regulating groundwater usage in the 1960s," said Jun Hayakawa, JICA's expert on water resource management. "By the early 1970s, the groundwater extraction and land subsidence stopped."
If most of Jakarta's groundwater usage can be prohibited, the city may soon see results, he said.
But this depends on how quickly the local and national governments can adopt regulations and provide alternative water sources, he added. That could be a major stumbling block.
Indonesian water expert Nila Ardhianie said around 65 percent of Jakarta's residents are forced to use groundwater because the piped water system only covers about a third of the population. But she puts a larger share of the blame for land subsidence on commercial use by hotels, malls and businesses.
Nearly every large government building also draws on deep groundwater wells, even though many have piped water, because groundwater is free for public buildings in Jakarta, according to Dutch think tank Deltares.
Under the current system, operated by a city-owned water company and two private firms, universal access to piped water would be achieved only by 2022, too late to stop groundwater extraction in time to brake further land subsidence, the report from the Dutch non-profits said.
Tokyo also had to build sea walls but they were raised gradually, said JICA's Hayakawa, suggesting Jakarta could do the same. "We need sea walls to protect the lives and assets of people in Jakarta," he said.
Source: http://jakartaglobe.id/news/flood-prone-jakarta-will-giant-sea-wall-plan-sink-swim/.
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