JAKARTA: The last time people prayed at the Waladuna mosque in the Muara Baru neighbourhood of North Jakarta, seawater had flooded the veranda during high tide, drowning the footpaths leading to the mosque in knee-deep water.
That was 18 years ago, residents told CNA. Not long after, people stopped praying at the mosque, built in the 1980s when the whole area was still sitting well above sea level.
Over the years, the ground beneath the mosque, as did the rest of Muara Baru, sank further and further.
Local residents said the massive flood which hit Jakarta in 2007, caused by a combination of persistent heavy rainfall and surging tide water, compelled the government to erect a wall to save the neighbourhood.
The mosque was deemed unsalvageable, and so the dike was built around it, standing 6m from sea level.
Today, the Waladuna mosque, which has become the unofficial symbol of Jakartas chronic land subsidence problem, stands lopsided and half-submerged in 1m-deep water during the day.
A colony of moss and mussels covered the mosques walls, running all the way to its dilapidated roof, providing a hint of where the sea level reaches when tide is at its highest.
Behind the dike, warehouses and factories had begun packing up and leave, leaving an empty plot of land sitting 3m below sea level.
The seawater constantly seeped through the cracks on the dike, local resident Mr Asmadi Widianto told CNA, drenching the neighbourhood and turning the ground into mud and swamp.
“Thats why the factories and warehouses moved. Trucks would get stuck in the mud and if the area is flooded during the rainy season, the contents of the warehouses would be destroyed,” he said.
The warehouses still standing now are largely empty, and the 37-year-old predicted that it would not be long before they are bulldozed to the ground.
Jakarta is one of the fastest sinking megacities in the world due to excessive groundwater extraction for drinking and other everyday purposes by the citys 10 million inhabitants.
Sixty per cent of Jakartas water demand is met by groundwater extraction, which compacts the soil around the aquifers and causes the grounds above them to sink.
Residents told CNA they are worried that the problem would be ignored with the eventual relocation of Indonesias capital to East Kalimantan.
However, the central government assured the people that it would continue to assist Jakarta to tackle its problems, including land subsidence.
READ: Will a great sea wall protect Indonesia's capital from coastal flooding?
RESIDENTS PLAGUED BY LAND SUBSIDENCE
Muara Baru resident Mr Mr Iwan Setiawan said it could take up to six months for the water to dry completely after a flood.
“The water had nowhere to go because the area is now below sea level,” the 75-year-old told CNA.
When Mr Setiawan first came to Muara Baru in 1967, the whole area was sitting 3m above sea level.
The area began sinking in the 1970s, he recounted, and by the early 2000s, the neighbourhood sat at sea level. Following that, the rate of land subsidence appeared to have speeded up, he said.
The average land subsidence affecting Jakarta is 1.15 cm a year, with some parts of the city sinking as much as 25cm annually, including Muara Baru.
According to a model conducted by Indonesias Bandung Institute of Technology (ITB), 95 per cent of the coastal areas in Jakarta could be entirely submerged below sea level by 2050.
Muara Baru, which currently sits 2m to 3m below sea level, could sink to more than 5m below water over the next 30 years.
With Jakarta facing chronic land subsidence, rising sea level from global warming, threat of massive flooding as well as crippling traffic congestion, the Indonesian government announced in August that it is moving its capital to East Kalimantan as early as 2024.
Over in the neighbourhood of Luar Batang, North Jakarta, roads and alleyways are filled with houses and shops sitting 0.5m to 1m below street level.
To compensate the sinking, residents have been adding ramps and steps to access their homes, while some completely abandoned the ground floor and build new levels entirely.
“We have to fix cracks in our houses every now and then because of the shifting of the grounds,” said Mdm Emmy Lestari, whose houses ground level now sits 2m below sea level.
“I built the second floor of my house about five years ago because seawater would creep in through the cracks of the dike and flood the neighbourhood.
“I hope the central government will completely solve this problem before they move. Otherwise, one day I might have to build a third floor.”
READ: Indonesia pledges US$40 billion to modernise Jakarta ahead of new capital
GROUNDWATER EXTRACTION A WIDESPREAD PRACTICE
Meanwhile, groundwater extraction continues to be a problem with no end in sight.
Since 1998, the number of household served by Jakartas piped water distribution system only grew from 44.5 per cent to 59.4 per cent in 2018, according to data from the Jakarta government.
“If Jakarta can stop extracting groundwater, the land subsidence could stop. This is because 70 per cent of land subsidence in Jakarta is caused by groundwater extraction,” Mr Peter Letitre, a groundwater management expert from Dutch-based think-tank Deltares told CNA.
The expert said Tokyo used to experience similar problem before the city stopped extracting groundwater in the 1970s.
“It is true that moving ministries and government offices will alleviate some of the pressures Jakartas aquifers have been facing.
“But the government has been weak on people who continue to extract groundwater,” he said.
Currently, there is no regulation to stop anyone, from individual homeowners to massive shopping mall operators, to carry out their own groundwater extractions.
“Even government offices use groundwater,” Mr Letitre said, adding that he is cautiously optimistic that the central government will continue to pay attention to the issue even as they move away from Jakarta.
“All major companies are headquartered in Jakarta. Jakarta will continue to be Indonesias business and economic hub, so the government will have no choice but to save Jakarta from sinking.”
Meanwhile, in some neighbourhoods served by piped water system, residents lamented that water supply is sometimes unreliable.
Cilincing resident Mdm Nur Hidayati said she is also doubtful about the water quality.
“We wouldnt drink water from the tap. It is often white and smells like chlorine. During the rainy season, the tap water is brown or yellow because it is mixed with dirt and soil,” she told CNA.
“Sometimes we only get running water during the night or sometimes very early in the morning like 2am or 3am.”
WITH A NEW CAPITAL, WILL JAKARTA BE NEGLECTED?
Dr Heri Andreas, a geologist at ITB who has been studying Jakarta's land subsidence for the past 20 years, worried that moving the capital would mean there would be less attention on the issue.
“Its like your wife is sick and you look for another wife. Of course the attention for the sick, old wife will be less,” he told CNA.
The expert said even with the central government still in Jakarta currently, not muRead More – Source