Physical and Spatial Condition
Geographically, Citarum River Basin lies between 106° 51’36” - 107° 51’ East Longitude and 7° 19’ - 6° 24’ South Latitude, covering a total approximate area of 11,323 Km². The almost 12,000-km2 Citarum River Basin covers 13 administrative areas of districts and cities within West Java Province, namely: Bandung, West Bandung, Bekasi, Cianjur, Bogor, Indramayu, Karawang, Purwakarta, Subang and Sumedang Districts, and Bandung, Bekasi and Cimahi Cities.
The boundaries of Citarum River Basin are as follows :
- To the north is the Java Sea
- To the south are Cianjur District and a part of Bandung District
- To the east are Garut District and a part of Indramayu and Sumedang Districts
- To the west are Sukabumi District and a part of Bogor and Bekasi Districts
Topographically, or based on its land forms or morphological classification, Citarum River Basin could be divided into 3 sections, namely upstream, middle and downstream sections. (1) The upper section of the basin comes in the form of a giant basin or popularly called Bandung Basin, located at elevations between 625 to 2,600 meters above sea level. (2) The middle section comes in various morphological landforms ranging from plains (elevations between 250 to 400 meters above sea level), undulating hills (elevations between 200 to 800 meters above sea level), steep slope hills (elevations between 1,400 to 2,400 meters above sea level) and volcanic edifices. (3) The downstream section is dominated by plains, undulating and steep slope hills in various elevations between 200 to 1,200 meters above sea level. All tributaries of the Citarum flow south to north, or they flow from their upstream regions in Mount Barangrang, Tunggul Hill and Canggah to the river mouth in the north coast (The Java Sea).
Morphological formation of Citarum river basin was the result of tectonic and volcanic activities which was followed by erosion and sedimentation developments. The morphological condition comes in various landforms ranging from volcanic edifices to hillsides. And plains in the upper regions of Citarum’s tributaries morphologically come in the form of volcanic edifices featuring characteristics of mild and mountainous relief at elevations 750 to 2,300 meters above sea level and at slopes 5 to 15% at the foot, 15 to 30% at the mountain slope and 30 to 90% at the peak. The river has a parallel-radial drainage pattern developed mostly in shallow and deep major water catchment areas as well as in springs located at slope breaks. The rock sediments are composed of young and old volcanic sediments, that is, tuff, breccia, lahar and lava.
The Climate in Citarum River Basin, like in most areas within West Java, is of a tropical monsoon with a relatively constant temperature and humidity throughout a year. The tropical monsoon climate is characterized by two distinct seasons, that is, rainy and dry seasons. A rainy season happens between the months of October and March and a dry season from June to September. Other months serve as a transitional period. The average temperature in lowland areas is around 27° C, while the minimum temperature in the river’s upper region of highland/mountainous areas stands at the average of 15.3°C.
The average annual rainfall varies from 1,000 mm in coastal areas to 4,000 mm in the mountainous areas of the upper basin. Almost 70% of the annual rainfall occurs during a rainy season. The distribution of the seasonal rainfall is mainly attributable to seasonal winds. The orographic effect of the southern mountain range on the rainfall variation appears dominant.
Geological condition of Citarum River Basin comes in different formation in its upstream, middle and downstream parts. Upper Citarum areas are mainly formed by tuff, lava, breccia and lapilli. While in its middle part, the formation lithologically consists of volcanic sediments, ancient lake-floor sediments in several locations and river alluvial sediments in narrow valleys along the major stream. The volcanic sediments are composed of tuffaceous sandstones, tuff shale, tuff breccias and agglomerates. While lake-floor sediments are composed of tuff clay, tuff sandstones, tuff gravel and tuff conglomerates. Alluvium is composed of clay, silt and sandstone and gravels. And they are generally made of tertiary sediments and materials from ancient volcanic eruptions. Downstream Citarum area is generally composed of tertiary sediments and materials from ancient volcanic eruptions.
Hydrogeological condition of Citarum River Basin as shown by the Groundwater Basin Map is estimated to have a total groundwater availability of 5,055 million cubic meters a year. Other than for domestic use, groundwater abstractions need government permissions and are subject to prevailing charges. In general the rate of groundwater abstraction is still below the ideal level, or still at 25%. In several locations, however, such as in groundwater basins of Bekasi-Karawang, Subang and Batujajar the rate has exceeded the ideal level. Nowadays, although the rate of groundwater abstraction in a groundwater basin of Bandung-Soreang is still less than the ideal level (still at 27%), but in several areas such as Majalaya, Ranca Ekek, Dayeuh Kolot, Leuwi Gajah and others, the rate has surpassed its ideal one, lowering the groundwater level and triggering a quite serious land subsidence in the areas.
Rivers. Citarum River Basin has 19 river streams which either empty into the north coast or join other rivers. Citarum is the major river in Citarum River Basin. The Citarum originates from Mount Wayang (Bandung District) and empties into Muara Gembong (Bekasi District). In accordance with the Presidential Decree Number 12 in the year 2012 on River Basin Territories, Citarum River Basin consists of 19 watershed areas.
There are 3 large dams, that is, Saguling, Cirata and Jatiluhur which provide hydroelectric power generation and serve local irrigation. The three are Saguling, Cirata and Jatiluhur Dams. All three are located in a Citarum River reach and 4 districts (Cianjur, Bandung Barat, Purwakarta and Karawang).
Technical Data of 3 Dams
|Location||Purwakarta District||Bandung Barat District||Purwakarta District|
||83.000 Ha||53.000 Ha||6.200 Ha|
|Constructed||1957 - 1967||1981||1982|
||3,5 Billion m3||609 Million m3||2,165 Billion m3|
|Impounds||Citarum River||Citarum River||Citarum River|
|Provisions||Agricultural irrigation, Source Water supply, Freshwater fisheries, Recreation and Water sports||Agricultural irrigation, Hydropower||Agricultural Irrigation, Source water supply, Hydropower|
||187,5 MW||1.400 MW||1.008 MW|
Sourcer : Balai Besar Wilayah Sungai Citarum, PSDA Office, West Java Province 2008
Jatiluhur Dam is located in Jatiluhur Sub-district , Purwakarta District, West Java Province (about 9 km to Purwakarta city center). Jatiluhur Dam is Indonesia’s largest dam. The government names it Ir. H. Juanda Dam, which offers a panoramic lake view of its 8,300 ha surface area. The dam was started to be constructed by a French contractor in 1957 and boasts 12.9 billion cubic meters a year of total potential of water sources. It is the first multi-purpose dam in Indonesia.
Jatiluhur Dam has 6 units of turbines with a total installed capacity of 187 MW and an average annual electricity production of 1,000 million kwh. It is operated by Perum Jasa Tirta II. In addition, under the management of Perum Jasa Tirta II Jatiluhur Dam serves the provision of water supply to a total of 242,000 ha of irrigated rice fields (with two growing periods in a year), raw water supply for drinking water, aquaculture and flood control.
In addition to its function as a hydroelectric power generator with the world’s largest spillway, Jatiluhur region offers convenient recreation facilities, including hotels and bungalows, bars and restaurants, tennis courts, billiard facilities, camping grounds, swimming pools and water slides, meeting halls, water recreation and sports facilities, playgrounds and other facilities. Water recreation and water sports facilities accommodate various activities such as rowing, wind surfing, recreational boating, water skiing, boating and others.
Jatiluhur Lake also provides its water area for floating fish cage industry which has become a water recreation destination due to its unique attraction. Also within the region, we can see Satellite Earth Station located around 7 km from Purwakarta city center. It is operated by telecommunication provider PT. Indosat Tbk and serves for international communications. The services are, among others, International Toll Free Service (ITFS), Indosat Calling Card (ICC) and international direct dialing. Jatiluhur Dam is accessible through the Purbaleunyi (Purwakarta-Bandung-Cileunyi) toll road by taking the Jatiluhur exit-gate.
Jatiluhur Dam Technical Data
|Type of dam
||Embankment, earth fill|
|Elevation at crest
||9,1 million m3|
||2,44 billion m3 at TMA + 107 m|
|Provisions||242,000 ha of irrigated rice fields, raw water supply for Jakarta, electricity generation of 187,5 MW, freshwater fisheries, Tourism and water sports development|
Saguling Dam is one of the large dams within Citarum River Basin which was built in 1981. At the beginning, Saguling Dam was intended to merely generate electricity. At the first phase, the hydroelectric power generator only has an installed capacity of 700 MW, which is expandable up to 1,400 MW in case of any rising demand in electricity in the future.
Saguling Dam is surrounded by hilly areas abundant with springs that feed the dam. This makes the dam have an irregular shape and numerous bays. The area used to be an agricultural land before the dam construction. Based on some researches, the dam’s water quality has significantly deteriorated due to water pollution resulted by agricultural and industrial productions, domestic activities and on the dam fisheries.
Up to 2008, Saguling Dam has accumulated sediments amounted to 84 million m3. The sedimentation rate in the dam is estimated at 4.2 million m3 or 4,819,664 tons a year. The sedimentation affects the function of the dam and the operation of hydroelectric generator. Additionally, industrial and domestic waste flown through the Citarum River reach worsens the sedimentation condition in the dam.
Saguling Dam Technical Data
|Type of Dam
||Embankment, rock-fill with watertight core|
|Height above riverbed
|Elevation at crest
|Reservoir total capacity
||2,79 million m3|
|Provisions||Agricultural irrigation, hydroelectric power 700 MW|
- Flood Elevation : 645 m
|Tributaries||Ciminyak, Cibitung, Cipatik, Cilanang, Cihaur, Cijambu, dan Cijenuk|
|Catchment area||2.283 km2|
|Average Annual Rainfall
|Rainfall by Design
|Average Annual Discharge||80,85 m3/sec|
|Preventive Discharge by Design (Debit Desain Pengelak)
Sumber : Balai Besar Wilayah Sungai Citarum, Dinas PSDA Provinsi Jawa Barat 2008
Cirata Dam was built between 1982 and 1987 and is surrounded by hillsides. Researches on the dam’s water quality find that the water has been heavily contaminated and has accumulated sediments. Up to 2000, sediments accumulated in the dam have reached 62.8 million m3. While the dam was designed to sustain an extreme limit of sediment volume of 79.3 million m3.. This rapid sedimentation process is the consequence of the rampant forest clearance occurring within Citarum River Basin.
Similar with two other large dams in Citarum, Cirata Dam has a function as a hydroelectric power generator. It is the largest hydropower in Southeast Asia. It has an underground power house construction with a total installed capacity of 8 x 126 Megawatt (MW) or 1,008 Megawatt (MW) and an average annual electricity production of 1,428 Giga Watthour (GWh).
The hydropower plant is operated by PT Pembangkitan Jawa Bali (PJB), a subsidiary of the state-run electricity company PT Perusahaan Listrik Negara (PLN persero), which distributes the electricity output through a 500 kilovolt (KV) transmission network across Java and Bali Islands.
Cirata Dam Technical Data
|Constructed||1982 - 1987|
|Type of Dam
||Embankment, concrete-face rock-fill|
|Catchment Area (DPS)||4.119 km2|
|Shape of catchment area
|Elevations||Maximum Surface Water : +223.00
Normal Surface Water: +220.00
Minimum Surface Water: +205.00
|Volume (m3)||Maximum Surface Water : 2,165 million
Normal Surface Water : 1,975 million
Minimum Surface Water: 1,177 million
|Luas Genangan (ha)||Maximum : 6,560
Normal : 6,200
|Anak Sungai||Cicendo, Cimeta, Cisokan, Cibalagung, Cikundul|
|Curah Hujan Rata-Rata Tahunan||1.895 - 2.250 mm|
|Probable Maximum Flood||6.642,3 m3/s|
|Manfaat||Agricultural irrigation, raw water supply , 1,008 MW hydropower station|
Source : Balai Besar Wilayah Sungai Citarum, PSDA Office West Java Province 2008