Sea levels are rising globally due to climate change, and many coastal cities around the world are at risk of being partially submerged by rising tides. Of all the cities threatened by the rising ocean, Jakarta, Indonesia is facing some of the most urgent threats. The northern parts of the city, which lies on the coast of Java, are less than 10 feet above sea level. With continued sea level rise, large portions of the city could be underwater within the next few decades.
Why is Jakarta sinking?
There are a few key factors that make Jakarta especially vulnerable to rising sea levels:
- Land subsidence – Jakarta is sinking at an extremely fast rate due to excessive groundwater extraction. The weight of tall buildings and depletion of groundwater causes the ground to compress and subside. The land is sinking by as much as 6-10 inches per year in some areas.
- Sea level rise – Global sea levels are rising 0.13 inches per year on average due to climate change. This further increases the risk of flooding in coastal cities.
- Loss of mangroves – Mangroves provide a natural barrier against storm surges and coastal erosion. Over the past three decades, over 70% of Jakarta’s mangroves have been removed for development projects.
The combined effects of land subsidence, sea level rise, and loss of natural buffers make Jakarta extremely prone to flooding today. Sea walls and other defenses are already insufficient to hold back floodwaters during high tide events.
What areas of Jakarta will be underwater?
Northern Jakarta is the most vulnerable, especially neighborhoods located in coastal areas or along rivers. Some specific districts projected to be partially submerged by 2050 include:
- Penjaringan – A coastal subdistrict that faces directly onto Jakarta Bay. It could be 80% underwater by 2050.
- Pademangan – A coastal region already experiencing routine flooding. Projected to be 5 feet underwater by 2050.
- Muara Baru – This subdistrict contains fish markets and ports along the bay. 70% could be inundated by 2050.
- Pluit – A heavily populated coastal area built on reclaimed swampland. Faces flooding threats from both the bay and the Ciliwung River.
Central Jakarta is also at risk due to its low elevation along the Ciliwung River, which regularly overflows its banks during monsoon rains.
How many people will be displaced?
If sea levels rise 3 feet by 2050, it’s estimated that 95,000 people across Jakarta would be displaced and forced to abandon their homes and businesses. With 5 feet of sea level rise, 340,000 people would be displaced in the city. That’s a population greater than the entire city of Orlando, Florida needing to relocate in less than 30 years. The following table illustrates the population displacement estimates at different sea level rise scenarios:
| Sea Level Rise Scenario | Estimated Population Displacement in Jakarta |
|---|---|
| 1.5 feet | 32,000 people |
| 3 feet | 95,000 people |
| 5 feet | 340,000 people |
The impact of hundreds of thousands of climate refugees will place immense strain on infrastructure and resources as displaced residents relocate farther inland. The loss of homes, property, jobs and community networks will also take an immense psychological and emotional toll.
What districts will remain above water?
Southern and central Jakarta districts located at higher elevations are expected to remain mostly dry:
- Kebayoran Baru
- Cilandak
- Mampang Prapatan
- Tebet
- Setiabudi
These areas may experience temporary flooding but will likely remain inhabitable. However, they will also face dramatic population increases and resource scarcity as climate refugees relocate from coastal neighborhoods. Transportation and infrastructure will be strained by the dense urban population crammed into a smaller livable area.
What is being done to protect Jakarta?
The government has proposed several massive infrastructure projects to try to defend coastal areas against rising seas:
- Giant sea wall – A 30 mile long, 60 foot high sea wall and levee system is planned to surround Jakarta Bay and block floodwaters.
- Offshore barrier islands – Artificial islands offshore could break waves and reduce coastal erosion.
- Massive pumping system – A system of pumps, reservoirs, and canals could theoretically pump out excess water during floods.
However, these projects are estimated to cost billions of dollars and their effectiveness is questionable. Critics argue the money would be better spent preparing evacuation systems and transitioning Jakarta to higher ground.
Other adaptation measures
Beyond mega projects, Jakarta is also pursuing other strategies to cope with the effects of climate change:
- Restricting groundwater extraction to slow land subsidence
- Restoring mangrove forests as natural coastal buffers
- Elevating roads and infrastructure to protect critical connections
- Implementing water storage and management systems
- Upgrading drainage systems and pumps
- Establishing climate refugee transition programs and settlements inland
- Researching crops that can withstand flooding and saline soils
Could Jakarta be abandoned?
If sea levels rise 6 feet or more by 2100, as some models forecast, protecting Jakarta with levees and pumps may become impossible. The government has already considered the possibility that the city may need to be eventually abandoned if coastal neighborhoods become completely uninhabitable.
One proposal is to build an entirely new capital city to replace Jakarta, located further inland on higher ground at central Borneo. While relocating the capital would be extremely complex, it may become the only option if large swaths of Jakarta are underwater.
Are other cities as vulnerable as Jakarta?
Jakarta is especially prone to flooding due to its unique geography and high rates of land subsidence. However, it is far from the only city threatened by rising seas. Other major coastal cities projected to face similar inundation risks include:
Bangkok, Thailand
Built on soft river deposits, Bangkok is sinking at a rate up to 2 inches per year. Sea levels could rise up to 3 feet by 2050, leaving much of the city underwater.
Alexandria, Egypt
Home to over 5 million people, Egypt’s second largest city could be mostly uninhabitable with just 3 feet of sea level rise. Rising seas have already flooded and salted agricultural lands.
Miami, United States
Miami streets already flood at high tides. The entire southern Florida peninsula is at risk from rising seas, not just the city itself.
Dhaka, Bangladesh
Built on the delta of the Ganges river, Dhaka is subsiding rapidly while facing rising rivers and sea levels. Severe flooding is expected by 2050.
Lagos, Nigeria
Rapidly sinking and exposed on a low coastal plain, Nigeria’s largest city is highly vulnerable to sea level rise projected in the range of 3 to 6 feet.
Other threatened coastal megacities
While less known than Jakarta or Miami, many other coastal cities with limited resources face severe risks from rising seas, including:
- Abidjan, Ivory Coast
- Chennai, India
- Dar es Salaam, Tanzania
- Surat, India
- Bandar Abbas, Iran
Climate change poses existential threats to coastal cities worldwide, especially in developing regions. Jakarta offers a dramatic example of how quickly an established megacity can face potential abandonment as seas continue to rise.
Conclusion
Jakarta, Indonesia is the coastal megacity facing the most imminent threat of partial submersion due to rising sea levels. The northern districts along Jakarta Bay and rivers are especially at risk, with hundreds of thousands of people likely to be displaced over the next 30 years. While massive infrastructure projects have been proposed, many experts believe the city may need to eventually be abandoned and relocated inland if sea levels rise more than 6 feet. Unfortunately, Jakarta is not alone – cities worldwide from Lagos to Miami face similar threats from climate change. Urgent action is required both to reduce greenhouse gas emissions and help threatened coastal communities adapt through measures like sea walls, drainage systems, and planned relocations.
