7- luthfan et al bsc vol-12 april 2014 (54-61)

Save Water, Save Jakarta Campaign as Land Subsidence Mitigation in Jakarta (Luthfan Harisan Jihadi, Abu Abdillah Ali, Zufialdi Zakaria, & Muhammad Bey Anural)

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PERSPEKTIF:

SAVE WATER, SAVE JAKARTA

CAMPAIGN AS LAND SUBSIDENCE MITIGATION IN JAKARTA

Luthfan Harisan Jihadi1), Abu Abdillah Ali1), Zufialdi Zakaria2), & Muhammad Bey Anural1)

1Student at the Dept. of Geological Engineering, Padjadjaran University, Jatinangor, Sumedang 2Lecture at the Dept. of Geological Engineering, Padjadjaran University, Jatinangor, Sumedang

ABSTRACT

Jakarta, a very populated capital city of Indonesia, was built above alluvial deposit which is currently subsiding relative to sea level at a high rate. As a result Jakarta becomes more often to be flooded with water that delivered from other regions and also the sea level rises relative to land and shoreline move toward the ground are increasing feasibility of tidal flood to occur. Consolidation process of the ground acts as a cause to the land subsidence in Jakarta. The fact is water needs in Jakarta is high due to its high population. Therefore, large amount in withdrawal of groundwater occurs and causes the ground to settle. In order to decrease the rate of land subsidence, groundwater should be extracted in a proper, more effective and efficient way. Younger generation is advised to save water using a fresh approach which is easy to be understood and accepted. In the future, people in Jakarta will consider that saving water as a norm which brings great benefit to their environment, Jakarta.

Keywords: Land subsidence; mitigation; counseling

INTRODUCTION

Jakarta is a capita l city of Indo-nesia, located in the northwest coast of Java. It is the most important city in Indonesia as an economic, cultural and political centre which populated

by over than 8 million o f people. All those inhabitants are living in the area which is about 625 km2, thus making Jakarta as the most populated city in Indonesia. Topographically, Jakarta has slopes ranging on 00 to 50 which southern most area has an

altitude of about 50 m above average number of sea level (Abidin, et al. 2007). Geologically, Jakarta is located on Jakarta basin. As mentioned by Yong et al. (1995), the Jakarta basin is composed of Quaternary deposits

which overlie Tertiary basement rock, and the top is considered to be the base of groundwater basin. The top layer in the Jakarta a rea is younger sediment that derived from stream sedimentation, alluvium, which composed by Kaolinite and Mont-

morillonite (Anisuzzaman, 2013).

Land subsidence is a decrease in elevation of land, relative ly to sea level. The cause could be as a natural process of sediments consolidation that derived by fluid loss, e g. groundwater, that not replaced by another fluid or as a process of

tectonics. However, the cause of land subsidence is mostly derived by human-induced issues, such as groundwater extraction, metal mining and oil-gas production (Hirose, et al. 2001). As mentioned by Primanita

(2010, after Ng, 2011), land subsidence could lead to other serious problems, e.g. cracks in the buildings and infrastructures, local groundwater systems damage, also lead into an increase of tension cracks on land and reactivate faults.

Over than a decade, a lot of data obtained from studies are showing a sign of land deformation in Jakarta. Moreover, land subsidence in Jakarta was already recognized in 1926 (Abidin, et al. 2007). Alluvium layer in

Jakarta, composed by Kaolinite and Montmorillonite , has a very high potential to deform, i.e . shrinking or

Bulletin of Scientific Contribution, Volume 12, Nomor 1, April 2014: 54-61

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swelling, especially in the northern coast of Jakarta (Anissuzaman, 2013).

Naturally, land subsidence would occur in the sediment layer, caused by its characteristic even without human inducement. The estimated subsidence rates in 1997-2005 are 1-10cm per year and reached 20cm per year, according to Abidin, et al.

(2007). Urban development in Jakarta is very fast. In a year, Jakarta population can increase in about a million. The growth also occurs in water needs which the problem is that

80% of Jakarta inhabitants are using underground water (United Nation, 2013). The report of groundwater use based on registered wells is a lready high, about 17 million m3 in average per year in 1900-1998, not included by unregistered wells which always

increasing as well as Jakarta develop-ment. As mentioned by Ardhianie (2011), recent minimum number of groundwater use could reach 270 million m3 per year. Excessive extraction of groundwater is increase-

ing the subsidence rate; the correlate-ion is mentioned in a survey by Abidin, et al (2011), that subsidence rate in Jakarta is related to the rate of piezometric water level in the m iddle and lower aquifer in Jakarta basin. Nowadays, land subsidence occurrence in Jakarta has become more and more problematic. In fact that Jakarta is re lative ly low to sea level and flat making it very susceptible to flood hazard, thus land subsidence make it even worse. Also,

land subsidence caused buildings to settle and damaged them. As the population grows in Jakarta, water needs also become much bigger resulting in excessive groundwater extracting, thus increasing the subsidence rate as Jakarta inhabitants

mostly use the groundwater to fulfill their water needs. Also, rapid population growth makes the hazard risk even higher. Therefore, a solution is needed to minimized the risk that caused by land subsidence.

METHOD

The method that is used in this study is a literatural research based on other previous studies that provide data which relevant with land sub-sidence in Jakarta. The secondary data are taken, then correlated by their relevancies and analyzed to

identify a problem, i.e. land sub-sidence in Jakarta. Thus, the cause of the problem can be pinpointed. Then, to design a solution is now possible . Main important points of the solution is determined, and designed to overcome the problem in any

means. Then, they are hypothetically described as a plan to be implement-ed in study area. Thus, a conclusion can be acquired in order to reduce or even solve the problem.

RESULT & DISCUSSION

Based on the data, we know about the relation of water usage and land subsidence rate in Jakarta. An increase in water usage by Jakarta inhabitants will increase subsidence

rate in Jakarta, and vice versa. In orde r to decrease the rate of land subsidence, groundwater should be extracted in a proper, more e ffective and efficient way. And in this case Jakarta inhabitants would take the major role .

As an idea, Save Water, Save Jakarta campaign is intended to reduce the water usage in Jakarta, as a mitigation of land subsidence. The campaign will spread the word about actual situation and cause of land

subsidence in Jakarta to the object. And also it will guide the object to understand and to act in a proper way in using water. In this case, young generation is treated as the main object, since their capability to learn is high. Also, young generation will be

the main subject in Jakarta develop-ment in a near future. The success parameter of this campaign is the annual rate of water usage, by a year or two o f its implementation. If the annual rate is reduced, the campaign


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is considered success. If else, the campaign should be continued or

revised. There are four important points in Save Water, Save Jakarta campaign: 1. The existence and purpose o f the

campaign have to be known by the object.

2. The knowledge has to be accepted by the object.

3. The object has to understand about the knowledge and know how to act based on it.

4. The campaign has to be in a form

that would be obeyed the object. In orde r to be known by the object, the campaign has to be distributed. By that means, any media that accessible and generally can touch the object, will be used. Social

sites on internet are considered as an effective and e fficient media, since they are free and used mostly by the object. The other advantages are that social sites can deliver the campaign in an interesting way since they

provide image, audio, and video distribution, thus increasing possibility to approach the object. Also, the sharing and promoting system is built in the sites and can be updated periodically. Therefore, communication with the object can be

maintained. The knowledge has to be packed in a way that the object will accept it openly. Still, in a way that not lessen the knowledge itself. Thus, as an example, visual based story te lling is

an ideal fo rm to be used s ince the object would have a tendency to like and remember something that fun and colourful, especially the object between 5-10 years old. Visual based story te lling can be in many forms, such as comic, mahwa, manga,

anime, or cartoon. Because o f that, there is no problem if the object has diffe rent taste in what she/he likes. Moreover, visua l based story te lling can be split into chapters and this way it becomes easy to read and can come

periodically, thus it would not be too boring to read.

After the object know and aware of the message that delivered by the campaign, the next step is to guide the act also by giving the object a deeper understanding about the message. The guide can be through formal education, i.e. elementary

school, junior high school, and senior high school. Direct communication between teacher and student would deepen the understanding. Also sometimes a little push is needed as a motivation, which is a reward or even

punishment. Those reward and punishment are taking in a fo rm as score, thus student, whether like it or not, have to learn about the knowledge in order to pass the exam. Religious reason also act as a guide as long as the object believes

that saving water is a virtue, and not to save water is a sin. In Islam, who commit excess is a sinner, Allah SWT hates the act of excess, including an excess in using water. Also, the one who wasteful is the brother of satan.

The message could be given through local mosque organization. A poster about Ayat that mention it can be placed in wudhu area or even inside the mosque (Figure 4). Ustadzs a lso can teach their student about the message. This way, the order to save

water will be obeyed by the object. CONCLUSION

Save Water, Save Jakarta campaign is needed to minimized the risk that caused by land subsidence. Younger generation is guided to save water by the campaign, using a fresh approach which is easy to be under-stood and accepted. In the future, people in Jakarta will save water, thus

reducing the groundwater usage. And in any means also reduces the risk o f land subsidence. *) Note: This paper was presented at: The 3rd International Symposium on Earthquake and Disaster Mitigation, ISDEM 2013, 17-18 December 2013, Yogyakarta.


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REFERENCES

Abidin, H. Z., Andreas, H., Djaja, R., Darmawan, D., Gamal, M. (2007). Land Subsidence Characteristics of Jakarta Between 1997 and 2005, as estimated using GPS surveys (p. 1). Published online: Springer-Verlag.

Abidin, H. Z., Andreas H., Gumilar, I., Gamal, M. 2011. Land Subsidence and Urban Development in Jakar-ta. Indonesia Country Report, 65-72.

Anissuzaman, Md., Muslim, D., Arif-

uzzaman, Shadrina, N. 2013. The Role of Clay Minerals on Land Subsidence: A Case Study in Ja-karta, Indonesia (pp.1, 4). 3rd International Conference on Ecological, Environmental and Biological Sciences, 188-191.

Ardhianie, N. 2011. Jakarta and Excessive Groundwater Exploitation. Taken from: http://www.amrta-institute.org/ news-a-press/73-jakarta-and-excessive-ground-water-

exploitation.html Badan Pusat Statistik. 2013. Banyak-

nya Penduduk Berdasarkan Has il Registrasi Menurut Wilayah di Provinsi DKI Jakarta. Taken from: http://jakarta.bps.go.id/index.php?bWVudT0yMzA0JnBhZ2U9ZGF0

YSZzdWI9MDQmaWQ9MzE= Hirose, K., Maruyama, T., Murdohar-

dono, D., Effendi, A., Abidin, Z. (2001). Land Subsidence Detection Using JERS-1 SAR Interferometry (p. 2). Singapore:

CRISP (Centre fo r Remote Imaging, Sensing and Process-ing), National University of Singapore.

Ho lley, R., Burren, R., Abidin, H. Z. 2011. Subsidence Mapping in Jakarata-PSI Processing of L-band

ALOS PALSAR Data. FRINGE2011. Ng, A. H., Ge, L., Li, X., Abidin, H. Z.,

Andreas, H., Zhang, K. (2012). Mapping land subsidence in Jakarta, Indonesia using persistent scatterer interfero-

metry (PSI) technique with ALOR PALSAR. International Journa l of

Applied Earth Observation and Geoinformation, 232 - 242.

United Nation, 2013. Jakarta, Indo-nesia. Taken from http://www.un.org/cyberschoolbus/habitat/profiles/jakarta.asps

Yong, R. N., Turcott, E. 1995.

Groundwater abstraction-induced land subsidence prediction: Bangkok and Jakarta case studies (pp. 2-3). International Symposium on Landsubsidence, IAHS, 234, 89-97


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Figure 1. Map of land subsidence in Jakarta period 1982-1997 (Centre fo r Environmental Geology, Geological Agency, ESDM; Anissuzaman, 2013)


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Figure 2. DifSAR Comparison between d iffe rent time span

in Jakarta, showing its land deformation (Ho lley, et al. 2011)

Table 1. Jakartas Population Through 1948-2006

Year Population (000)

1948 est. 2000

1961 2973

1971 4579

1980 6503

1990 8259

2002 8379 2003 8603

2004 8725

2005 8864 2006 8961

(Lo and Yeoung, 1995; BPS Jakarta, 2007; in Abidin, et al. 2011)

Table 2. Jakartas Population Through 2007-2010

Year Population

2007 7554461

2008 7616838

2009 8523157

2010 8524152

(Badan Pusat Statistik, 2013; Dinas Kependudukan Provinsi DKI Jakarta)


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Figure 3. Showing extracted groundwater by registered wells annually in Jakarta, (Hirose, 2001; Sudibyo, 1999)

Figure 4. Logo o f Facebook, Twitte r, Blogger, and Instagram. All rights reserved

Figure 5. Showing an example o f comic strip that containing a message

about saving water awareness. (Taken from: http://waterthenewpetrol.iesmanacor.cat/comics.html)


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Figre 6. Showing an example o f comic strip that containing a message

about saving water awareness. (Taken from: http://waterthenewpetrol.iesmanacor.cat/comics.html)

(Taken from: http://quran.com/17/26-27)

Figure 7. Ayat that mention about the act excess.

7- luthfan et al bsc vol-12 april 2014 (54-61)

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