Alex Hekman, business manager Water bij Sweco en lid kernteam Delta technologie Topsector Water


Goed sanitair gaat voor klimaatbescherming

Het is een complexe puzzel in het Indonesische Jakarta, waar vele vervuilde rivieren uitmonden in een stijgende zee. Tel daarbij op dat op grote schaal schoon grondwater onder de stad vandaan gepompt wordt waardoor deze wegzakt – en je komt tot een complex watervraagstuk waar Nederland een handje bij moet helpen. In dit artikel uit onze Engelstalige Aquatech special vertelt Alex Hekman, business manager water bij Sweco, welke belangen spelen, en welke belangen het meest urgent zijn om aan te pakken. Schoon sanitair heeft volgens hem prioriteit boven klimaatbescherming. Samen met ingenieursbureaus RoyalHaskoning DHV en Witteveen + Bos wordt een stappenplan opgesteld te bescherming van Jakarta.



Sanitation should precede flood protection in Jakarta

Indonesia’s capital city Jakarta needs to be protected against future flooding, as floods are expected to increase due to extreme land subsidence and global warming. Dutch engineering consultancy Sweco is involved in the National Capital Integrated Coastal Development (NCICD) masterplan, better known as the Giant Sea Wall, that should be constructed in the bay north of the city around an offshore retention lake. But first, Jakarta’s huge sanitation problems have to be addressed to avoid an environmental and economic catastrophe, says Sweco’s business manager Alex Hekman.

Jakarta is not only increasingly prone to floods because of climate change, inadequate sewerage, and bad water management, the city is also sinking at a rate of up to 20 centimetres per year due to deep groundwater extraction. Alex Hekman explains: “There is no clean water in Jakarta. Officially, only 3% of Jakarta’s ten million inhabitants are connected to proper sewerage. Actually it is 2%, as only one third of this system is actually working. Most of the 10 million inhabitants use poorly maintained septic tanks in their homes. 20% of the population still practice open defecation. Therefore, 700 tons of human waste ends up in the environment every day (source: World Bank).”

“Large investments are needed before water from the pitch-black rivers that flow through and around the city can be used as source for drinking water. That is why people extract groundwater, especially near the coastline. Consequently, the soil subsides, with more flooding as a result. Rich people can afford to buy expensive drinking water in bottles or blue gallons, which comes from upstream water reservoirs. They use groundwater to shower or wash their clothes, but that is getting polluted now as well. People living in the slums will have to use tap water, which is brown and has to be boiled before drinking, with all health risks associated with that.”


According to Alex Hekman there should be more awareness about the dangers of continued groundwater extraction. “Providing a safe source for drinking water has to start with improving sanitation. In 2012, the Japanese have developed a masterplan, though laborious negotiations have not led to significant results yet. Jakarta has been divided into fifteen zones, but talks about implementing the plan in two of these zones are going on for five years now. However understandable (realising the project is expensive), it is necessary to start executing the plan as soon as possible. Doing nothing is not an option, and will cost Indonesia’s economy as a whole 6 billion dollars a year. In the meantime it would be advisable to start a parallel trajectory to try solving problems on a much smaller, and economically more feasible scale.”

‘Doing nothing is not an option, and will cost the Indonesian economy as a whole 6 billion dollars a year’

Mr Hekman, among others, showed initiative and brought fragmented Indonesian ministries and governments, as well as potential donors together to start tackling the sanitation issue, but the outcome was disappointing. “Donors considered Jakarta to be a rich city capable of solving these problems on their own. Still, we did manage to get sufficient funding to carry out some research. We wanted to know how bad the situation really was and what we could do to change that. The first step was creating a roadmap to address the lack of sanitation, and prevent pollution of the planned retention lake north of Jakarta.”

“Gradually momentum changed and grew”, says Mr Hekman. “A responsible representative of the Ministry of Planning considered the sea wall and the danger of an environmental catastrophe actually as a blessing, as it finally gave him convincing arguments to accelerate Jakarta’s sanitation. Now Jakarta Sewerage is one of the national infrastructural priority projects, which hopefully provides the necessary momentum. From the beginning we knew we would have mountains to climb. Having reached this goal, we are in fact proud of it. We hope to start a substantial pilot project any time soon in a large area along the coastline.”


The aim is to build a drinking water supply network there, linked with the sanitation nobody wants to pay for. “If we can offer drinking water at a lower price, that could make realisation of the whole project more feasible, and at the same time stop Jakarta from sinking further down.” Alex Hekman stresses that industries should comply with the rules. “Enforcement will become increasingly important. Those companies build water treatment plants, but don’t use them to save money. Only when they know their plant will be inspected, they turn the system on for a little while. And sewage systems should be installed in new neighbourhoods immediately, but unfortunately that usually is not the case.”

Sanitation is one of many preconditions for the NCICD flood protection masterplan to work, and probably the most important one. Together with Witteveen+Bos and RHDHV (consultancy and engineering services) Sweco is involved in designing the retention lake, which should buffer the outflow from Jakarta’s thirteen rivers, and the giant sea wall around it. Building it will take approximately fifteen years from now. “We are aware that we can’t get the entire lake clean in time, but a very innovative engineer has come up with some excellent solutions, like dividing the basin into compartments and diversion of the polluted water. This way, I am sure we can reduce the impact of the pollution, and even significantly improve the water quality in a large part of the lake, revitalizing the deteriorated fishing grounds close to the coast. These measures cost money, but it is a solution that won’t create an environmental disaster, as pitch-black water from the rivers cannot flow back to the city.”

Sweco designs and develops the communities and cities of the future. The results of their work are sustainable buildings, efficient infrastructure and access to clean water. The next step is to move from the preparatory phase to implementation and construction, with all kinds of new challenges. Sweco is looking forward to face that challenge.



Climate change adaptation calls for a stepwise approach

Since 2000, successful adaptation to the impacts of climate change on water is one of the greatest challenges the Netherlands has been and is still facing. There is more precipitation, and in order to store all that extra water the country will have to build more storage facilities. Nowadays, the focus is very much on cities, which coincides with Sweco’s ‘Cities of the Future’ approach. The Dutch engineering consultancy has developed a stress tool to find out what damage (extremely) heavy rainfall can do. “Together with our colleagues from Ecorys, we have added an economic perspective. The tool helps authorities to address the severity of the damage, and how to translate it into a multi-annual implementation and investment program. Time is on our side.”

“It would not be wise to implement a five year urban adaption programme in the foreseeable future, if you cannot include necessary adaptations in existing urban restructuring plans”, says business manager Alex Hekman, who adds: “Our experience is that adaption is still mainly linked to the water domain, but we should connect it to the urban, spatial domain as well. Restructuring project managers usually don’t have a clue about the possible impacts of climate change. Off course they should, because they ought to know which parts of the city wide puzzle they have to solve before they will be able to make adaption part of their projects. The only way to do it economically is to follow a stepwise approach: adapt one street or neighbourhood each year, until the puzzle is complete in 2050.”

This autumn the new Dutch Delta plan for Adaptation has been made public. The focus is very much on analysing hotspots and adapting them gradually. “We share the same ideas. You can’t make a city adaptive overnight. We should look at long-term maintenance cycles and investment programs to make our cities and country future proof.”

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