LAND USE AND WATER QUALITY RELATIONSHIPS IN THE CILIWUNG RIVER BASIN, INDONESIA Melati Ferianita Fachrul Diana Hendrawan Anita Sitawati Dept. of Environmental Engineering Trisakti University Gd. K. Lt. 7 Jl. Kyai Tapa No.1 Grogol, Jakarta 11440, Indonesia
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ABSTRACT
Ciliwung River is a water body which has variable allotments. The changes of allotment in water catchment area directly or indirectly will change its water quality, and also will decrease its beneficial uses as well. For 30 years (1970-2000), the sizes of the wetland area and of the water body decreased to 55% (5,774 Ha). Water Quality Index (WQI) of Ciliwung river has decreased to 33,38% during 12 years. The decrease of WQI in the Ciliwung river water has been caused by landuse alteration. Keywords: river, water quality, landuse alteration INTRODUCTION
The Ciliwung River is running along a line from South (Bogor) to North through the city. The upstream is located in Puncak Mountain, runs through the Bogor city and on through Jakarta. The downstream is located at Marina Beach in Jakarta Bay. The length of the river from upstream to downstream is about ± 76 km, with the catchment area of about 322 km2. The Ciliwung River is used as the source of the water supply system. Due to the condition of the river in Jakarta, nowadays the function of this river has been changed. In Bogor this river is still used as the water source of the drinking water treatment plant. Ciliwung River is contaminated mostly by domestic wastes and its water cannot be processed into drinking water, water for recreation, plantation irrigation or fresh water cultivation. In the last two decades, condition of the river basin of Ciliwung Upstream has gotten worse due to uncontrolled land use changes. The conversions from agricultural to settlement uses have significant impact on the magnitude of variation of discharge. In lowland rice field areas, due to a wide gap between the economic land rent between settlements and rice field uses, a large amount of highly suitable land for rice field in Babelan sub-district have been converted. Issues of water quality and quantity are at the forefront of environmental issues in Indonesia, as reflected in pressing public concerns about floods, landslides, sedimentation, dry season flows in drier regions, and pollution of both groundwater and
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surface water – along with related problems such as increasing competition for irrigation among farmers, and escalating water charges for domestic consumers. One of the major concerns of government, donors and public alike are how to manage land and water resources effectively – to maintain clean supplies while avoiding floods and erosion. Importantly this raises issues over the rights, responsibilities, costs and benefits of land management and water use. Indonesia is not alone in dealing with these questions. Recognition is growing internationally of the links between upstream land management and downstream water quantity, reliability and quality. The Ciliwung River waters from upstream to downstream are heavily polluted by gray water from households, commercial buildings, together with discharges from industries, pesticide and fertilizer run-off from agricultural land, solid waste, and fecal matter from overflowing or leaking septic tanks. Therefore, its water quality is being altered. The changes of the land use without taking note of the Area Planning or Regional Planning will change the land function and increasingly the quality and quantity of waste entering to the river. THE PURPOSE OF STUDY
The purpose of this study is to analyze the change in land use and land cover in the Ciliwung River basin during 30 years (1970, 1980, 1990 and 2000), assess the water quality change during 12 years (1993 and 2995), and describe the relationship between land use change and water quality in the Ciliwung River Basin RESEARCH METHODOLOGY
The study location along the Ciliwung river basin was divided into three segments. They are, segment I as the Up stream location (Cisarua Bogor, Gadog, Kedung haling and Kelapa Dua), and segment II and segment III as K.H. Mas Masyur and Teluk Gong. Table 1 shows the sampling point locations and geographic coordinate positions of the study. The locations and sampling points are shown in Figures 1 and 2. Table 1. Locations of Sampling Stations on the Ciliwung River
No. 1 2 3 4 5 6 7 8 9 10
Location Cisarua Bogor Gadog Kedung Halang Kelapa Dua Kalibata Kampung Melayu Manggarai Guntur KH Mas Mansyur Teluk Gong
Geographic Position 06o42’11,2” SS ; 106o59’26,6” ES 06o39’05,1” SS ; 106o52’02,1” ES 06o33’45,8” SS ; 106o48’27,4” ES 06o21’06,2” SS ; 106o50’21,5” ES 06o15’29,3” SS ; 106o51’38,3” ES 06o13’34,4” SS ; 106o51’51,3” ES 06o12’45,3” SS ; 106o51’28,3” ES 06o12’26,8” SS ; 106o50’36,2” ES 06o10’11,5” SS ; 106o47’42,5” ES 06o47’49,5” SS ; 106o43’54,9” ES
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Figure 1. Study Locations and Sampling Points
Data analysis of land use and land cover along the Ciliwung river basin was performed using the aerial photo maps from 1970, 1980, 1990 and 2000. The satellite map analysis results show that there has been land use alteration. The water quality analysis was conducted on primary data based on the water quality measurements during 1980, 1990 and 2000. The water samples were analyzed using Water Quality Index (WQI) as described by Ott (1978). Thus, the use of an appropriate Water Quality Index (WQI), in which a set of parameters perceived to be important in characterizing water quality are related to a common scale, will be more beneficial for administrative and management purposes and for meaningful communication with the public. The computation of general WQI of river water is based on the procedure adopted in International Sanitation Foundation – Water Quality Standard (INSF-WQS) by Ott (1978). A total of eight parameters : ie, DO, pH, BOD5, Nitrogen, Phosphate, Temperature, Turbidity and Suspended Solid were selected with the weighting factors referred from Ott (1978) with some minor modification. RESULT AND DISCUSSION
In general, land use is classified into five (5) classes (1) land use for agriculture, (2) land use for wet land and water body, (3) land use for settlement, (4) land use for
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industrial estate, and (5) land use for business services. The table below indicates the change of land use in Ciliwung river basin from 1970 to 2000. Table 2. Land Use Change of Ciliwung River Basin during 1970 – 2000 1970 % area of river basin
Land Use Ha
1980 % area of river basin d Ha
1990 % area of river basin Ha
2000 % area of river basin Ha
UNDEVELOPED AREA Land for Farming and Green Open Space
15,312.13
39.55 13,817.70
35.69 13,066.61
33.75 10,478.55
27.07
Wet land and Water Body
10,375.86
26.80 8,656.87
22.36 5,222.77
13.49 4,601.29
11.88
25,687.99
66.35 22,474.57
58.05 18,289.38
47.24 15,079.84
38.95
12,060.00
31.15 12,385.21
31.99 13,984.18
36.12 14,410.05
37.22
Sub Total DEVELOPED AREA Settlement Industry
193.58
0.50 1,711.24
4.42 2,470.07
6.38 3,883.20
10.03
Business Services
774.32
2.00 2,144.86
5.54 3,972.25
10.26 5,342.79
13.80
Sub Total Total
13,027.90
33.65 16,241.31
41.95 20,426.50
52.76 23,636.04
61.05
38,715.89
100.00 38,715.88
100.00 38,715.88
100.00 38,715.88
100.00
The table above indicates a time span of forty (40) years. During these times, the undeveloped plot of land decreased drastically. This is indicated by land use change percentage for agriculture and green open space area, and wet land and water body as well. In 1970, the percentage of land use for the two classes is 66% of total river basin or about 25,687,99 hectares. However, in 2000, the area of undeveloped land use is only 38% of total river basin or leaving only about 15,079,84 hectares. The high settlement development in the river banks decreases the capacity of water body. This condition affects the decrease of river basin water quality. Starting from 1980, the land use for settlement increased fast particularly in South Jakarta and city of Depok. During 1990-2000, the settlement area development has spread widely to Bogor and Ciawi which are in Bogor Regency. Meanwhile, the development of industrial and business-services areas occured mostly in the downstream region, in Jakarta. As a main result, when maps of land use from 1970 to 2000 are studied, it is seen that the composition of undeveloped and developed areas has been reversed. The developed area comprising land use for settlement, industrial estate and trade service has risen two fold. In 1970, the percentage of land use for these three classes is about 33% of the river basin area or approximately 13.027,90 hectares. Meanwhile, in 2000 this area rises to 61% of the river basin or about 23.636,04 hectares. The change of land use from agriculture to settlement and commercial use make the land surface impervious. This will affect the rise of waterflow, streamflow
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capacity and absorbtion into the ground. Furthermore, this condition will impact the accumulation of river water pollution. The following illustration depicts the fluctuation of undeveloped land use area.
18,000.00 16,000.00 Un Using Area
14,000.00 12,000.00 10,000.00 8,000.00 6,000.00 4,000.00 2,000.00 0.00 1970
1980
Land Farming and Green Open Space
1990 Year
2000
Wet land and Water Body
Figure 1. Change of Natural Land Use in Ciliwung River Basin during 1970- 2000
16,000.00 14,000.00
Using Area
12,000.00 10,000.00 8,000.00 6,000.00 4,000.00 2,000.00 0.00 1970 Settlement
1980 Industry
1990
2000
Business Services
Figure 2. Change of Developed Land Use Ciliwung River Basin in 1970-2000
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INTERNATIONAL CONGRESS ON RIVER BASIN MANAGEMENT
Table 3. Land Use around Ciliwung River
Land use Open Space Settlement Industry Street Office Park Trade Park
Upstream 21% 51% 3% 12% 2% 11%
Middle Area 13% 58% 10% 7% 7% 5%
Downstream 2% 62% 14% 4% 11% 7%
THE WATER QUALITY OF CILIWUNG RIVER
The change of land use, pervious areas and high activity will directly cause a change in water quality. The analysis results for the measured water quality during 1993 and 2005 are shown in Figure 3.
Water Quality Index (WQI)
100 80 60 40 20 0
1
2
3
4
5
1993
95
95
90.5
90.5
79.5
2005
63.9
51.9
46.68
70.67 64.07
6
7
8
9
10
82
66.5
70.5
91
49.43
46.8
41.81
47.59 49.54
Station
Figure 3. Comparison of Water Quality Index of Ciliwung River on Each Research Station in 19932005.Information : Station (1) Cisarua, (2) Gadog, (3) Kedung Halang, (4) Srengseng Sawah, (5) Kalibata, (6) Kampung Melayu, (7) Manggarai, (8) Guntur, (9) Karet Tengsin and (10) Teluk Gong
In Figure 3, it is seen that during a 12 years timespan there is a decrease in Water Quality Index Value (WQI). The index in 1993 ranges from 66,5 to 95,0 (PoorMedium category), while in 2005, it ranges between 41.81 – 70.67 (Poor – medium category). The decrease of WQI value in station 1 is 32.74%, station 2 is 25.61%, station 3 is 28.62 %, station 4 is 42.65%, station 5 is 41.28%, station 7 is 39.58%, station 8 is 25.67%, station 9 is 33.62% and 54.05% for station 10. Generally, a decrease of 33.38% occurs in the WQI of Ciliwung River during the 12 years period. This decrease depicts that there has been change to the water quality of Ciliwung River caused by change of land use.
Figure 4 Land Use Change in the Ciliwung River Basin (19970 – 2000)
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CONCLUSION
1.
2.
3. 4.
The water quality index of Ciliwung River ranged between 66.5–95.0 (medium to excellent category) in 1993, while, it ranged between 41.81–70.67 (medium to excellent category) in 2005. It was concluded that the overall water quality of the Ciliwung River decreased by 33% during 12 years. The decrease of WQI value indicates that the water quality change is caused by land use change. In 1970, the undeveloped plot of land area is 66% of the total of river basin or about 25.687,99 hectares. But in 2000, the undeveloped use is about 38% of river basin are or about 15.079,84 hectares. In a 30 years period (1970 – 2000), the wide of land use is decreasing to 55 % or about 7774 Ha. THIS SENTENCE IS NOT CLEAR. PLEASE REPHRASE. Land use around Ciliwung River varies in upstream, middle and downstream areas. Vacant land in upstream area is 21%, 13% in middle area and 2% in downstream side. The land use for settlement, industrial area and business district are increasingly high in downstream area. REFERENCES
Anonim. 2002. Kaji Ulang Penataan Ruang Kawasan Bopunjur/Kabupaten Bogor dalam Rangka Mitigasi Banjir DKI Jakarta. Direktorat Jenderal Penataan Ruang, Departemen Permukiman dan Prasarana Wilayah. Anonim. 2002. Pemaduserasian Rencana Tata Pengaturan Air DAS Ciliwung – Cisadane terhadap Rencana Tata Ruang Kawasan Bopunjur dan Jabodetabek. Direktorat Jenderal Penataan Ruang, Departemen Permukiman dan Prasarana Wilayah. Badan Pengelolaan Lingkungan Hidup Daerah (BPLHD) Propinsi DKI Jakarta. 2001. Rencana Kerja Daerah Prokasih Visi 2005 Ciliwung. Boon, P.J., P. Calow, and G.E. Petts. 1992. River Conservation and Management. John Wiley & Sons.. Direktorat Reboisasi dan Rehabilitasi. 1978. Rencana umum DAS-DAS di Pulau Jawa dan Madura. Direktorat Reboisasi dan Rehabilitasi. Direktorat Jenderal Kehutanan. Departemen Kehutanan. Jakarta. Hidartan and Agung H. 1994. Pemetaan Geomorfologi Sistimatis Untuk Studi Geologi, PIT 23 IAGI, Jakarta. Nemerow, N.L. 1991. Stream, Lake, Estuary and Ocean Pollution. Van Nostrand. Ott, W.R. 1978. Environmental Indices. Theory and Practice. Ann Arbor science, Washington, DC. Purwadhi S H. F. 2001. Interpretasi Citra Digital. PT. Grasindo, Jakarta Rozi, M.F. 2002. Pendekatan Sistem Dalam Pengaturan Penggunaan Lahan untuk Menurunkan Indeks Fluktuasi Debit Sungai. Skirpsi Jurusan Manajemen Hutan Fakultas Kehutanan Institut Pertanian Bogor, Bogor.