Jakarta is sinking. It doesn’t perhaps gain the same international exposure as a city such as Venice, but nevertheless, the ‘Big Durian’ – as the Indonesian capital is locally known – is subsiding at a rate of around ten centimetres per year, although it varies wildly across the city.

‘Subsidence in coastal areas of Jakarta is mostly caused by excessive groundwater extraction,’ explains Dr Hasanuddin Abidin, from the Bandung Institute of Technology. While Jakarta faces the same threat from rising sea levels as much of the rest of the low-lying world, rising demand from over ten million thirsty residents means the city’s water supply is reliant on the extraction of groundwater – hence, the dramatic rate of subsidence. Flooding by the encroaching tides, as well as the city’s 13 rivers, is now putting the lives of millions of people at risk. ‘Relatively significant coastal subsidence in Jakarta is disastrous,’ continues Abidin, ‘since during high tides they create coastal flooding in the relatively dense population coastal areas of Jakarta. The government has erected sea dykes along the coast but, since the dykes keep subsiding, during high tides the coastal flooding is still happening.’

An ambitious project is underway to drain the city’s rivers into a harbour-side freshwater retention lake, where an enclosing seawall keeps the water level below that of the sea. ‘At first glance, you would think this seawall is to keep the sea out of the city,’ says Gijs van den Boomen, managing director of KuiperCompagnons, who developed the urban design plan for the waterfront. ‘This is true, but there’s a lot more to it than that.’ Instead, the lake allows the rivers to empty naturally, preventing water from backing up into the city. Furthermore, wastewater treatment can purify the river water and turn it into an acceptable source of drinking water. ‘If we don’t stop the groundwater extraction by providing a piped water supply, the subsidence will continue,’ says Van den Boomen. ‘It’s not a sustainable solution. So, included in the plan is the creation of a piped water supply network.’

From the air the development will resemble the infamous Indonesian ‘Garuda’  (Image: KuiperCompagnons)

Officially entitled the National Capital Integrated Coastal Development, the project more commonly goes by the name ‘Great Garuda’, due to the construction taking the shape of the Garuda bird – the national symbol of Indonesia. ‘It’s very important to stress that the design of the new waterfront city is not the goal in itself, although it is helping to create enthusiasm,’ says Van den Boomen. ‘This plan is not about shiny glass towers and a new central business district. It uses those ingredients as a means to an end to realise a new future for Jakarta. Four and a half million people are at stake here – their lives, livelihoods, and their future. This is what we call the Robin Hood design principle: we build for the rich to save the poor.’

This article was published in the February 2016 edition of Geographical magazine.