Towards a blue city
Possible solutions for the risk of flooding in Jakarta
Figure 1. May 7th 2013, Jakarta flooded. Jakarta Globe.
Course: Interdisciplinary Project
Khymo Moestadja - Earth Science 10749349
Quirine Cohen - Earth Science 10516794
Quico Schmitz - Political Science 10805532
Stijn van de Kamp - Social Science 10773193
Coordinators: Dr. Crelis Rammelt & Dr. Coyan Tromp Tutor: Roosmarijn Bakker
Expert: Dr. Kenneth Rijsdijk
Words: 7530
Abstract
Jakarta is the capital of Indonesia, with a population of 30 million people (DKI Jakarta, 2014). Just as many other coastal cities around the world, the threat of floods is increasing, putting the livelihoods of millions of people at risk. The main causes for this threat are land subsidence, sea level rise and an increase of social vulnerability. Moreover, government authorities are not addressing these problems properly. However, two possible solutions are developed; the Great Garuda Project and the Spatial Plan 2030. The Great Garuda project consist of a 40 km sea wall spread over 17 different islands. The project will be developed in three phases over a period of 30 to 40 years. The negative aspects of this project can be the water stagnation of the artificial lake causing contamination of drinking water and the loss of jobs of fishermen. The Spatial Plan 2030 is a plan to integrate upstream and downstream activities in water-related management. It needs to increase the community participation and awareness of long-term climate change adaption. In order to implement this plan, corruption should be act upon. With regard to corruption, one of our recommendations is to improve law enforcement, other recommendations will improve both technical and structural measures. This is why two umbrella institutions need to be formed by the Indonesian government, one to assess technical problems and the other to assess structural problems.
Content
§1 Introduction 4
§2 Theoretical Framework 5
§2.1 Causes of land subsidence 6
§2.2 Effects of land subsidence 7
§2.3 Social problems of Jakarta 10
§2.4 Governance issues of Jakarta 11
§2.5 The Great Garuda project 14
§2.6 Spatial plan 2030 15
§3 Methods 16
§3.1 Flood areas and flood risk areas 2013, 2014 and 2015 in Jakarta 20
§4 Results 22
§4.1 GIS maps 2013, 2014 and 2015 22
§4.2 Negative aspects current projects 22
§5 Discussion 24
§6 Conclusion 25
§7 References 26
§1 Introduction
Floods are a major threat to coastal cities, causing economic damage and loss of lives. More than 50% of the world’s population lives in cities and these cities will increasingly be affected by flooding due to several factors such as climate change, land subsidence and socio-economic changes (Douglass, 2010). Climate change is projected to lead to a rise in sea level, more intense rainfall and increased peak river flow. Therefore, the urgency for adaptation to flooding has gained much attention (IPCC, 2007). One of the cities where flood events are increasing in frequency is Jakarta (Smith & Petley 2009). With an inner city that covers about 660 km² and a metropolitan area that covers about 7.500 km², Jakarta is one of the largest cities in the world. The number of inhabitants in the inner city has been growing rapidly from about 600.000 in 1945 to just over 10 million in 2015. This growth was even larger in the metropolitan area of Jakarta (JMA), which resulted in more than 30 million people living there in 2014, which accounts for about 11% of Indonesia’s total population. This immense flood of people has caused the city to become the ninth most densely populated urban region in the world, with about 15.170 people per km². Almost all of these migrants came to Jakarta for economic reasons, as the city offered hope for finding employment. Nowadays, Jakarta is het center of Indonesia’s economy and, based on 2005 data, it accounts for 24.63% of Indonesia’s total GDP (DKI Jakarta, 2014).
These statistics indicate that Jakarta is the largest and most important city of Indonesia, and even one of the most important in Southeast Asia, which makes it especially important to protect this city from flood threats. Jakarta has a long history of riverine and coastal flooding, and it occurs more frequently and intense. For example, in 2007, a flood in Jakarta took 80 lives and drove 430.000 people out of their homes. Those inhabitants were left homeless, displaced and got ill (Steinberg, 2007).
These floods are caused by several drivers; the first driver is the sea level rise of 0.2 m per year due to climate change, with a possibility of 1.8 m additionally by 2025 (Jevrejeva et al. 2016). Another driver is its geographical location; Indonesia lies in a seismic zone surrounded by many active volcanoes, which increases the risk for natural hazards such as floods, drought, fires, tsunamis (Hartono et al., 2010) and seasonal rainfall intensity (Caljouw et al. 2005, Steinberg 2007). The last major driver is the fast land subsidence rate in the area. Land subsidence has been increasing since 1982, when it was measured for the first time (Ward et al., 2011). If these events continue, the flooding frequency will increase even more.
At first we will look into the causes of the increase of flooding from an earth-scientific point of view. Taking this into account, the social effects of these flooding’s will be investigated. At last, the governmental measures will be assessed and recommendations will be made. With this interdisciplinary case study we address the problems and give recommendations on how the city of Jakarta can protect itself from the threat of floods. When these recommendations and measures will have a positive effect on the mitigation of flood hazards, it can be an addition to further research on protecting coastal cities from floods.
This research will give an answer to the following research question: What are the causes, effects and solutions for flooding’s in Jakarta and what recommendations can be constructed in order to mitigate flood hazards? In order to answer the research question, several sub questions will be resolved.
These sub questions are:
What are the causes of floods in Jakarta?
What are the effects of floods on the inhabitants of Jakarta?
What are the effects of increasing water rising in Jakarta on the infrastructure of Jakarta?
What policies are being implemented in response to rapid water rising in Jakarta?
§2 Theoretical Framework
In this theoretical framework we are determining the underlying theories and concepts of our interdisciplinary research. These theories and concepts are critical in order to comprehend the possible solutions for the increase of flooding’s in Jakarta. First, the main cause and effects of land subsidence will be explained. Secondly, the social problems that will occur after a flood will be analyzed. Taking these causes and effects into account, the governance issues will be elaborated. Finally, two possible solutions will be clarified.
§2.1 Causes of land subsidence
In Jakarta, four different types of land subsidence can be distinguished and can be categorized in natural and anthropological causes. Land subsidence is caused by tectonic movement, groundwater extraction, load of construction and natural consolidation of alluvial soil. The natural causes are tectonic movement and natural consolidation of alluvial soil. Both groundwater extraction and load of construction are anthropological causes, but natural effects can worsen load of construction. Due to great urban development, groundwater extraction is the most influential factor and tectonic movement the least impacting cause (Abidin et al., 2011).
Natural land subsidence
Tectonic and volcanic activities, isostatic sediment loading or natural compaction of Holocene deposits can cause natural land subsidence. Land subsidence caused by tectonic and volcanic activities can only occur in areas where volcanoes and faults are active (Chaussard, Amelung, Abidin, & Hong, 2013). Jakarta lies between the Australian and Sunda plates, which are currently active (Tjia 1978). Moreover Indonesia is surrounded by Circum-Pacific belt, the world’s greatest volcano belt (Israel 2010).
Natural compaction of Holocene deposits can either result from dewatering and increase of the stress in unconsolidated sediments or result from oxidation and shrinkage in organic deposits. When this occurs, large areas will subside by a homogenous rate of a few mm/year. Since Jakarta lies on the coast and is an alluvial plane, compressible deposits are common. Sediment loading is a natural cause, but can also be brought by anthropological actions. When sediments are loaded it induces compaction of clays resulting in land subsidence with rates up to 5 cm/year and decreasing exponentially per year (Chaussard et al., 2013).
Groundwater extraction
Jakarta lies on a Quaternary sediment of 250 m thick and consists of an upper (<40m), middle (40 – 140m) and low aquifer (140 – 250m). Most of the groundwater extraction extracts water from the middle aquifer. There are two ways of groundwater extraction, deep extraction (>40m) or shallow extraction (<40m). According to Ali (2011) about 64% of water needed in Jakarta is done by one of these extraction manners (Abidin et al., 2011). Mostly shallow extraction techniques are employed by the population through digging wells and therefore the extraction rate per well is relatively low.
Deep extraction is conducted by the industry, has a high extraction rate and is more concentrated. In the west and northeastern part of Jakarta, land subsidence is mainly caused by industrial groundwater extraction where the soils have high compressibility. The groundwater extraction was measured up to 22 Qabs (million m3)in the year 2007 (Abidin et
al., 2011). Moreover the illegal groundwater extraction cannot be measured and can account for 50% of the groundwater extraction (Abidin et al., 2001).
Most of the groundwater extraction leads to deepening of the piezo metric water level inside the middle and low aquifers, since deep extraction has a higher extraction rate (Abidin et al., 2001). According to Abidin et al. in a research done in 2011 the rate of piezo metric water level deepening in the lower and middle aquifer is related to the subsidence rate. The declining trend of piezo metric heads can be seen in figure 1.
Measurements done in 2011 suggest that the land subsidence rates are about 0.1 – 1.9 m/year over a period from 2002 to 2007. Although it is suggested that with an increase in population the groundwater extraction will also increase, the relation cannot be simplified. On a shorter time scale the groundwater extraction fluctuates greatly in contrary with long-term subsidence and is not yet fully understood (Abidin et al., 2011).
§2.2 Effects of land subsidence
Land subsidence has a great effect on the city of Jakarta and can be seen in different ways. Due to land subsidence, cracks in infrastructure or buildings can be formed and houses can sink. It also has an influence on the drainage systems and flooding areas. It can change the stream flow, expand flooding areas, break drainage systems and increase the inland intrusion of seawater. Coastal flooding during high tides can also enhance the negative effects on health and sanitation (Ward et al., 2011).
Flooding
First the definition of a flood; a flood is an overflow of water that inundates land which is normally not covered by water, according to The European Union Floods Directive (Mostert & Junier, 2009). Flooding may occur as an overflow of water from water bodies, such as ocean, lakes or rivers. The water overtops or breaks levees and this results in water that escapes its natural boundaries. It can also occur due to accumulation of precipitation on saturated ground in an aerial flood (Christopherson, 2015). Some floods can be local, impacting a neighborhood or community, or very large, affecting entire river basins (Christopherson, 2015).
According to a research from IPCC (2007) sea level will keep rising and the rainfall intensity will be more due to climate change, this will cause more flooding all around the world. The risk of major flooding in Jakarta is increasing, due to the high subsidence rate along the coast and its location near major rivers. Currently the northern area of Jakarta is the most vulnerable for flooding (Ward et al., 2011). Chaussard (2013) estimates that within 20 years the costal part of Jakarta will be below sea level, taken a coastal subsidence rate between 9.5 cm/year to 21.5 cm/year into account. Since 2000 there have been four major floods in Jakarta, in 2002, 2007, 2013 and 2014. During every flood, more than 20.000 people needed to be evacuated and deathly victims occurred.
According to Ward et al. (2011) an area of around 3400 ha with a return period of 100 years will be flooded, if the current subsidence rate and sea level rise will continue. The damage that these floods will generate will be 4.0 billion euro. When calculated over 1000 years, this damage will increase by a factor of 1.3.
The flooding in Jakarta mainly occurs due to its position, which is on a 5000-year-old alluvial fanlike plain, composed of the debris of the Salak, Pangrango and Gedeh volcanoes.
The alluvial plain was positioned just above sea level, on seashore that is slowly expanding due to the sediments that are transported by the rivers from upstream and it is taking the shape of a large bay. Because the alluvial plain is just above sea level we characterize this as a lowland area (figure 2) (Caljouw et al., 2005).
Lowland areas are potentially vulnerable for natural flooding by waterways; the Ciliwung River is the largest waterway in the alluvial plain. In the dry season there is not a high risk for flooding, the discharge of the rivers are low. But during the rainy season the risk of flooding is high. In this time of the year the rivers carry the bulk of their sediments. Due to the rapidly increasing population the built-up environment extended enormously, which have led to obstruction and deterioration of the drainage system. There is a reduction in the discharge capacity of the river due to obstruction in the natural drainage system (Caljouw et al., 2005).
Figure 2. Outline map of the Bay of Jakarta with the hinterland. Scale 1:1,000,000. Dark grey area: Alluvial plane (Caljouw et al., 2005)
Furthermore, Jakarta’s population increased from 2.7 million in 1960 to 9.6 million in 2010 according to the BPS of Jakarta (2010). Many buildings were built to house this rapidly increasing population. The asphalt pavements and concrete buildings are reducing the infiltration capacity, this means that rainwater can only flow directly into the river, as a result the river peak flows and discharge are increasing (Hartono et al., 2010).
As a final result, the amount of rainfall that cannot be retained by the soil and river may now cause flooding (Hartono et al., 2010). Meanwhile, due to deforestation and increasing peak flows, the amount of sediments that are transported by the river is increasing.
This will cause fewer problems in the upstream sections because the transportation capacity is generally higher over there. However, in the lower section, the velocity of the water is lower which is causing the sediments to settle, which decreases the cross-section. Without proper maintenance the cross-section will continue to decrease and the flooding’s are more likely (Caljouw et al., 2005). Besides the sediments that settle, many of the man-made constructions such as floodgates, bridges and drainage systems are also causing a narrowing in the flow cross-section, which can create backwater effects that can cause flooding upstream.
§2.3 Social problems of Jakarta
Jakarta faces a vast amount of social problems. Increasing urbanization and immigration, a widening gap between rich and poor and a vast poor population of 700.000 inhabitants. Furthermore increasing environmental stress results in intensified flooding.
Inequality is a very pressing issue in Jakarta, the gap between rich and poor households is widening. Mismanagement of the government is one of the main causes of the increasing inequality (Texier, 2008). This will be further explained in paragraph 2.4, governance issues. Many other factors such as over urbanization and increasing immigration are also contributing to the problem of increasing inequality. Rising over urbanization and immigration results in insufficient housing opportunities for the poor population of Jakarta forcing them to live in informal settlements on flood prone areas, making these inhabitants vulnerable to flooding (Sagala et al, 2013). Moreover natural disaster intensifies inequality since poor households are more susceptible to flooding than more affluent households (Steinberg, 2007)
As described before, Jakarta is considered one of the most vulnerable cities to climate-related disaster. Flooding, land subsidence and sea level rise can result in loss-of live, infrastructure and damaged economies. Furthermore over 60% of the urban population lives in informal settlements in high-density and flood-risk areas (Steinberg, 2007). At present Jakarta has approximately a 400,000 poor population and around a 300,000 near poor population. Most of the poor live in slum areas in several parts of Jakarta, which are greatly susceptible to floods (Firman et al, 2011).
These parts of Jakarta are susceptible to floods because they are often built near riverbanks or on deltas. These slum areas are called Kampungs, which are informal settlements. Most of the Kampungs are very high in density with 600 people per hectare.
Furthermore most of these Kampung lack sufficient sanitation or running water (Steinberg, 2007) and are built since poor households cannot get access to normal housing.
The rich reside in luxury condos and housing for middle class is provided through the real-estate sector (Steinberg, 2007). Therefore the poor population is Jakarta is vast and highly vulnerable to flooding. The fact that 60 % of the population of Jakarta is forced to live in informal settlements that are highly susceptible to flooding is a result of inequality and shows how vast the societal problems are that Jakarta is facing.
An important reason that the poor population cannot sufficiently cope with the flooding in Jakarta is because they lack adaptive capacity (Steinberg, 2007). . ‘’Adaptive capacity is when there is a process, action or outcome in a system (household, community, group, sector, region, country) in order for the system to better cope with, manage or adjust to some changing condition, stress, hazard, risk or opportunity. ’In the case of Jakarta the households try to cope with flooding’ (Smit, et al., 2006). Poorer households have a low adaptive capacity because they do not have the tools to manage the hazard. They have no money or power to change their situation. Moreover when inhabitants make a living from the land on which they live on, for example fish and farm cultivators, they are even more vulnerable because their livelihood is dependent on their geographical location (Brouwer et al, 2007).
Moreover, flooding can have a huge impact on the health of the urban population (Kovats et al, 2008). Health is an important factor to assess the societal problems of Jakarta, because health is crucial to the well being of the inhabitants of Jakarta. The main concerns for climate-change impact on human health are changes in freshwater resources, food supplies and increasing extreme weather. Flooding is a result of increasing extreme weather and has impact on the accessibility to freshwater resources and food supplies (Kovats, 2008). The food insecurity can lead to malnutrition and thus diseases for the inhabitants of the informal settlements (Sverdlik, 2006). Furthermore health can be negatively affected because of contamination of the drinking water with chemical and heavy metals. This happens when the floodwater containing chemicals infiltrates drinking water-wells and poisons the population (Kovats, 2008).
In addition to contamination of the drinking water and lack of food supplies, people in flooded areas are more prone to infectious diseases like, cholera, cryptosporidiosis, typhoid fever and diarrheal disease (Kovats, 2008). They wade in the water which contains the diseases and the bacteria of the flood water stream into the water-wells (Kovats, 2008). A disease that is occurring more frequently in flooded areas is leptospirosis.
Leptospirosis is a potentially fatal disease that is caused by rat-urine in flooded areas. This disease results in a high fever and vomiting and is a very substantial danger for flood-risk areas (Sverdlik, 2006).
§2.4 Governance issues of Jakarta
Paragraphs 2.1, 2.2 and 2.3 show that Jakarta has multiple problems regarding the threat of floods, like land subsidence, climate change and social vulnerability. Almost all of these problems could be partially or completely solved with better governance. However, improving the governance in a corrupt and decentralized system like Indonesia's is a very difficult task. One of the biggest policy issues regarding technical measures, like dikes and flood canals, is that they are very expensive and require a lot of political and institutional commitment to actually be implemented (Simanjuntak, 2011). A good example to show Jakarta’s troubled decision-making process is the recent flood management plan named ‘East Flood Canal’ (EFC), a construction that aimed to discharge water if floods occur. The design of this plan was finished in 1973, but construction did not begin before 2003. According to Simanjuntak (2011), who examined the decision-making process of the EFC, there are multiple factors that delayed its construction for more than 30 years. First, ‘Master Plans I, II and III’ were created between 1973 and 1997, for flood control and drainage in Jakarta. These plans were created in collaboration with governments and institutions from the Netherlands and Japan. Unfortunately, a lack of resources, coordination, accountability and adaption resulted in a delay of any technical measures. Only when the Decentralization Law was enacted in 1999 the decision-making process changed, which should have resulted in the implementation of the EFC plan. But even after that, an extreme event (the floods in 2002) was needed as a catalyst for taking action. In 2003, after 30 years of postponing, the construction of the EFC started and was finished in 2011. Unfortunately, it could not prevent the floods in 2013, because the canal was not properly cleared of sediment and garbage. Also, the city’s population had outgrown the numbers on which the plan was based. This process is a glaring example of just how difficult and time-consuming it is to implement technical measures that counter problems like land subsidence (§3.1) or floods (§3.2) in the city of Jakarta.
Another problem which influences both land subsidence and runoff problems is that the development of the city has been led by the market instead of the government. This means that new development of the area is in the hands of private investors, instead of the national or regional authorities. These investors only solve run-off problems for their own lands, which only shifts the problems to other areas.
This private development has caused the conversion of about 16.000 ha of land from rural type to urban in the last 15 years, an increase of about 18% (Rustiadi, 2007). This causes the ground in these areas to become more impermeable, which effects water flows and the ability of the ground to absorb (rain)water.
This urban development also causes the load of construction to increase, which in turn increases land subsidence. Atop of all this, Indonesian government officials refuse to hold the (international) developers responsible for the almost total deforestation of JMA. This is mainly because they are afraid it will scare off future foreign investors, which could harm the economy. Another reminder of the corruption in Indonesia’s national and regional government (Texier, 2008).
Urbanization is not only a problem in JMA itself, but also in regions that are located more upstream on the Ciliwung River, like Bogor and Depok. Because more land is being converted to urban type, the run-off to the river is much higher in times of heavy rainfall. Clearly, this causes even more problems for JMA. The issue here is that all provinces in Indonesia have their own policy on water management, which has caused this problem to become inter-governmental and very difficult to solve (Sagala et al, 2013).
The problems that are addressed in paragraph 3.3, inequality, social vulnerability and health issues, are also not addressed properly by Indonesian authorities. They favor short-term civil engineering (technical) measures, like canals and dikes, above long-term solutions. The reason for this is that these measures are directly observable, and thus very strategic to appease public concern about the floods (Sagala et al, 2013). This creates a false sense of security, which makes Jakarta’s population think it is safe, while the people, properties and infrastructure are still very much at risk, which was most recently illustrated by the 2013 floods. The authorities also focus too much on the extreme flood-events. The big ‘five-year period floods’ are not the only problem, especially to the poorest people of the city. Sagala et al (2012) showed that there are some parts of Jakarta where floods occur almost every year. Unfortunately, these floods do not get a lot of attention, because the affected areas are inhabited by the lower classes of society. This is a problem that needs more attention from government authorities.
This brings us to the final and probably biggest problem of Indonesia’s (and JMA’s) water management policy, which is political and administrative fragmentation as a result of the country’s decentralization policies. This caused a vast amount of institutions to have some authority over the country’s water management.
Some examples of these institutions are the Ministry of Public Works (responsible for the river system), the Public Works offices at a provincial level (tasked with the construction and maintenance of drainage systems), BAPPENAS (responsible for the planning of national land-use), BAPEDAL (carries out river monitoring), the BKSP (responsible for coordinating, planning and monitoring of JMA’s development) and several other Ministries like Agriculture, Environment and Forestry.
This web of organizations causes for even more inter-governmental problems and conflicts of interest (Ward et al, 2012). This makes the decision-making progress very indecisive, ineffective and uncoordinated. And so it is very clear that this system lacks an agency or institution that oversees the water management of JMA as a whole, to properly address the threats and problems mentioned in paragraphs 2.1, 2.2 and 2.3.
Fortunately, government authorities have developed some solutions during recent years, both technical and structural. Although is it clear that Jakarta has a lot of problems in dealing with the threat of floods, some measures have already been taken that could provide solutions for the future. An example are the laws and regulations that have been installed in recent years to deal with flood-related issues such as the Spatial Planning Law, the Water Law, the Disaster Management Law, the Spatial Plan 2030 and the Great Garuda Project. The last two are the most important and will be explained in paragraph 2.5 and 2.6
§2.5 The Great Garuda project
In order to permanently protect Jakarta from flooding’s, the Jakarta Coastal Development Strategy team has developed a plan together with the Dutch government and several Dutch architecture companies. This plan is called the Great Garuda Project and was developed in 2007. The project consists of a 40km long, 24m tall sea wall and will spread out over 17 islands, to protect Jakarta from sea level rise in the future. It will have the form of the Garuda, a great eagle with outstretched wings, which is the national symbol of Indonesia. It is estimated that the project will cost nearly 40 billion USD and will take 30 to 40 years to complete (Priyambodho, 2015). The project started on the 9th of October and costs 40 billion dollar (Indonesia Investments, 2014). Once finished, the project will also function as a new part of the city, as it will be home to 300.000 inhabitants (Priyambodho, 2015).
The project will consist of three different phases, with different purposes. The first phase, phase A, will strengthen the current sea wall and river dikes. This is will serve as a short-term solution in order to withhold the current flooding’s. In phase B a new sea wall will be build and will close the western part of the bay. The last phase will only be done if land subsidence cannot be decreased by other efforts in the area. When this needs to be done, the eastern part of the bay will be closed. These three phases will create a new lake in the bay, which will provide the population of Jakarta of clean drinking water that will lead to less groundwater extraction (Priyambodho, 2015). When the groundwater extraction will decrease the land subsidence rate will also decrease, deteriorate the risks of flooding’s. Moreover with the new retention lake, great pumps will be built to pump the extra water away in order to artificially keep the sea level low. These pumps will have a capacity of 750 m3/s.
§2.6 Spatial plan 2030
Another plan to protect Jakarta from floods constructed by the government is the Jakarta Spatial Plan 2030 installed in 2008. In Jakarta flood risks are often related to upstream activities, such as deforestation and market-led city development. When making a plan to protect Jakarta from flooding the whole system of water catchments has to be taken into account (Caljouw et al., 2005). Upstream river basin rehabilitation projects and reforestation programs have already been set up, this will provide a framework for future developments, but its success will depend completely on basin scale implementation. The need to integrate upstream–downstream activities in water-related management is stressed in the Jakarta Spatial Plan 2030. It specifically stressed the need to integrate upstream-downstream management of the Ciliwung River Basin, which would address a lot of problems regarding land subsidence and runoff-problems. It also claims that more non-technical measures are required, like increasing community awareness and participation through public involvement campaigns, which are carried out by government institutions in cooperation with NGO’s. This would be a huge step in decreasing the social vulnerability of poor populations. These campaigns could also explain the dangers of illegal groundwater extraction to Jakarta’s population, but this also means that the authorities should provide these people with another way of getting sufficient water supplies. The Spatial Plan 2030 also promotes a more long-term view regarding climate change adaptation, conservation and hazard zoning. With this plan, Jakarta aims to be a leading example for southeast Asia (Ward et al, 2012).
§3 Methods
For this report, the core method consists of a literature study, conducted from different disciplinary angles. The disciplines from which the literature study is conducted are political science, earth science and social science. After individual research from the three disciplines, the results are combined in an interdisciplinary study. The interdisciplinary integration methodology of Repko (2012) functions as a guideline in combining the three disciplines.
The floods in Jakarta form a problem which meet the criteria to need an interdisciplinary approach. According to Repko (2012), these criteria are 1) The research question addresses a societal issue, 2) the societal issue is of high complexity, 3) no single discipline can address the problem completely and 4) important insights from all disciplines are needed to come to a sufficient conclusion.
It is clear that the flooding of Jakarta is a societal issue, as it affects a considerable number of individuals within a society and also takes cooperation of these individuals to come to a solution. Also, since it is necessary to gather information from both earth sciences, social sciences and political sciences to be able to answer our research question and give recommendations to improve Jakarta’s governance system, criteria 3 and 4 of Repko (2012) are met. Finally, the issue is complex in such a way that results from one discipline could possibly form an obstruction for the results of another discipline. For example, technical solutions from earth sciences or political sciences could form an obstacle for the problems encountered by the social scientist. This is why common ground between the disciplines needs to be found, using the integration technique of organization.
In order to integrate the disciplines and add to the credibility of this study, common ground between the used disciplines needs to be discovered. There are five integrating methods to integrate a disciplinary research, namely expansion, organization, transformation, extension and redefinition. This research used organization in order to find common ground. The integrative technique of organization singles out an underlying commonality in meaning of different disciplinary assumption or concepts (Repko, 2012). The commonality between the various disciplines in this research study is to reduce the negative effects of flooding in Jakarta in order to sustain quality of life. In figure 4 is a visualization of the created interdisciplinary understanding.
In addition to a literature study Geographical Information System (GIS) was used to assess flood-risk areas. These maps show the flooded areas in Jakarta in 2013, 2014 and 2015 and the flood risk areas in 2014. Moreover a DEM was used in order to map the height differences in the area, this knowledge can be used to draw further conclusions about the causes of flooding in Jakarta and differences over the years. GIS was used in order to visualize the scale and location of the flooding’s in Jakarta and grand a geographical overview.
With the used methods we were able to conduct an interdisciplinary research. The disciplines were a good fit to come to the final recommendations. First the causes and effects were being viewed out of an earth-scientific view. After having established the causes of flooding the effects on the people in Jakarta were highlighted, to integrate the social relevance. At last the current policies were being viewed. With all this information and insights from the different disciplines some recommendations were made. In those recommendations successful integration of all the different disciplines was conducted.
§3.1 Flood areas and flood risk areas 2013, 2014 and 2015 in Jakarta
All maps were made in ArcGIS and were derived from the online database in ArcGIS.Map Geometry type Feature class Geographic coordinate system
Derived from
Flood area 2013 Point Single
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Flood risk area 2015 Polygon Single
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§4 Results
In the results the main findings of this research project are displayed. Furthermore three maps made with GIS give a visualization of the flooding that Jakarta had to cope with from the period 2013 to 2015. Moreover the negative aspects of current projects, which the government of Jakarta is using to mitigate flood risks, are examined.
§4.1 GIS maps 2013, 2014 and 2015
As can be seen in figure 5, 6 and 7 the flood areas are mainly around the largest river in Jakarta: the Ciliwung river. Other flood areas can be seen in the northeast and northwest area. This corresponds with our findings, since the northern part is the lowest part of Jakarta and it is a seashore. Most of the other flood areas on our GIS map are around rivers. When we compare those flood areas from 2013 and 2014 with the areas that are most prone to floods we can see a resemblance. The areas with the highest risk of a flood are around the Ciliwung river and in the north of Jakarta, which is the lowest part of Jakarta. When we compare the flood risk areas from 2014 with 2015, an increased surface is noticeable. The flood risk areas in 2015 are more concentrated and they have a higher density. The flood risk areas of 2014 have become larger in 2015 and thus more people are at risk. When the three maps are compared you see an increase in flooded areas, this will become more in the future and more people will be at risk.
§4.2 Negative aspects current projects
As described in paragraph 2.5 and 2.6 both projects were created with the intention to minimize the threat of increasing floods in Jakarta. These projects include a new sea wall to protect the coast, creating an artificial lake with drinking water and fishing purposes and protective governmental measures that include the whole system of water catchment in Jakarta. During this research negative aspect of both projects emerged, these aspects will be explained in this paragraph.
Negative aspects of the Great Garuda Project
There are several problems if the Great Garuda project will be build. As described in §3.1, groundwater extraction will lead to land subsidence, which will increase the risk of flooding in Jakarta. Furthermore land subsidence and groundwater extraction can lead to sedimentation of the main rivers in the area. This sedimentation has a negative influence on the Great Garuda project and can lead to land deformation. This can occur when sediments are deposited in the artificial lake. Usually the sediments can flow into the sea but due to the newly build seawall the natural flow will be disturbed. Since the underlying layer is unstable the additional weight of the sediment can subside the layers underneath the seawall (Pacheco-Martínez et al. 2015). Another negative effect can occur when the water will stagnate in the artificial lake that will be created after phase B of the project. A broad coalition of Indonesian scientists, land activists and local residents claim that the bay will turn into an artificial lagoon of trapped freshwater. According to Alan Koropitan, professor of oceanography at Bogor Agricultural University, the outer sea wall and manmade island will create a greater pollution and sedimentation as water is trapped inside the dike, rather than being flushed out to sea. The cleansing process that is naturally occurring will disappear. There is no, to little sewage treatment for the river water pouring into the bay. The surrounding rivers are heavily polluted and they need to be widened, dredged, cleaned and protected with new concrete barriers before they can finish the Garuda Project. The attempt to sanitize Jakarta’s waterfront could have the opposite effect and deteriorate the freshwater
in Jakarta.
Not only will this water stagnation lead to contamination of the drinking water, it will also lead to a non-suitable living area for fish. Since these fish will disappear, thousands of fishermen will be unemployed. Another negative social effect will mainly have an impact on the poor population in the area. On the Garuda, 300.000 living spaces will be build, but will only be affordable for the rich population. Therefore the poor will still need to live on the mainland where many areas still will not be protected for flooding’s.
Moreover this will lead to a separation of complete neighborhoods, since the poor population will live more than ten miles away of the Garuda.
Negative aspects of the Jakarta Spatial plan 2030
The intentions are good, but with the current political system of Indonesia, it will take years or maybe even decades, before all parts of the plan will be implemented and act upon. This could turn out to be disastrous for the economy of the city because, as calculated by Budiyono et al (2015), the annual expected damage due to river flooding in Jakarta will be around 321 million USD per year under current circumstances.
§5 Discussion
In this interdisciplinary research recommendations were formed in order to mitigate flood hazards after investigating the causes, effects and solutions of the increase of flooding’s in Jakarta. However, we have found several shortcomings in order to give a sufficient and achievable recommendation for mitigation flood hazards.
During our research we have found that the main insufficiency was the inability of travelling to Jakarta. This would have improved our research by gaining more detailed information about the living conditions in the kampung and their experiences when a flood occurs. Moreover up-to-date measurements could have been done, improving the knowledge about current rates of land subsidence and the increasing amounts of sediments from upstream. If we had more up to date measurements our findings of the negative effects of both land subsidence as sediment build up could have been more accurate.
Subsequently the information available in the online database of ArcGIS was insufficient to create accurate maps of both the spatial knowledge as the flood risk areas. Indonesia is not yet investigated enough by scientist who have published their findings in the online database. Furthermore the information that was available, was published by Indonesian scientists who have written their publishments in Indonesian. This made it difficult to translate and process these findings into a map.
At last the implementation of the policy recommendations about the mitigation of flood hazards is uncertain as a result of much corruption in the Indonesian government. New president Yudhoyono is trying to act upon corruption by installing the anti-corruption commission KPK, but it seems that fraud, extortion and bribery are so deeply ingrained in Indonesia’s culture that it will prove to be very difficult to eradicate this problem. If this problem is not solved in future years, it could prevent the implementation of a lot of recommendations.
In further research we would analyze if the results of our findings are based on accurate measurements. Furthermore we would develop a control panel group in order to investigate if the government correctly implements our recommendations. This to avoid the current delays that Jakarta is now facing with the policies due to the corruption. Moreover, to get a better view of the social situation in Jakarta we would have to do fieldwork in Jakarta and do intensive interviews with the people in Jakarta. Besides, we would also include interviews with experts regarding the technical techniques and policy makers to get better insights in
§6 Conclusion
The risk of flooding is very high in Jakarta. These floods have many anthropological and natural causes and can be minimized by the right government policy. The main causes for flooding are the geographical location of Jakarta, climate change, increasing population with a build-up environment that is decreasing the discharge capacity of the rivers, the amount of sediments that is increasing and clogging the rivers and the man-made constructions that are narrowing the flow cross-section. A lot of these aspects ensure that Jakarta is prone to flooding. If illegal groundwater extraction, contamination of the rivers and the urbanization can be reduced, the risk will decrease significantly. Furthermore inequality should be taken care of because poor households are more affected by flooding. The poor population is more vulnerable to flooding than middle/high class population for a number of reasons. Inequality between poor and middle/rich class is one of the main reasons for the high vulnerability of the poor population. Texier claims that inequality is a result of mismanagement. Therefore current policies should be changed in order to save many lives. Inequality results in great differences in housing. The poor population lives in Kampungs in flood-risk areas in high densities. This makes them more vulnerable to flooding and thus to the dangers of flooding. In addition the location of Kampungs is often in flood-risk areas. Furthermore the adaptive capacity of poor households is low because they do not have sufficient tools to manage the flooding. They lack the resources to change their situation. Flooding can also have a huge impact on health. The health of the poor population of Jakarta is expected to be the most negatively affected by floods. Drinkwater-contamination with chemicals and heavy metals can poison the population. Freshwater resources and food supplies could also be cut off, resulting in malnutrition. Moreover infectious disease such as diarrhea and leptospirosis could occur in flooded areas causing disease that could be fatal.
In conclusion, our recommendations for the protection of Jakarta against the threat of floods include: 1) Some that have already been mentioned in the Spatial Plan 2030, such as the integrating of upstream-downstream management of the Ciliwung River Basin, 2) more non-technical measures, like increasing community awareness and participation through public involvement campaigns, which will increase the preparedness of Jakarta’s population and 3) the adoption of a long-term view towards climate change adaptations. These measures would be a big step in the right direction, but even more has to be done.
For instance, the only non-technical measure the Spatial Plan mentions is the increasing of public awareness, but it fails to address other non-technical measures like 4) decreasing community vulnerability, 5) the installment of flood warning systems, 6) the growing of mangrove forests along the coast and 6) the improving of law enforcement.
Other recommendations are 7) an improvement of the drainage systems, 8) water-retention areas, and 9) flood monitoring. The final recommendation 10) is that the Indonesian government should form one institution that oversees the designing and construction of technical measures, so that projects like the Eastern Flood Canal and the Great Garuda Project can be completed faster and more efficiently, and one institution for solving the city’s social problems like inequality. We believe the city of Jakarta should follow these recommendations if it wants to protect itself from the dangers explained in this interdisciplinary study.
§
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