Rajang River
Encyclopedia
The Rajang River is a river in Sarawak
, Malaysia. The river is located in northwest of Borneo
and it originates in the Iran Mountains. The river flows approximately 563 km to the South China Sea
, making it the longest river in Malaysia.
The upper part of Rajang River is also known as Batang Balui by the Orang Ulu. Some of the more important tributaries are the Katibas River
, the Balleh River
, the Bangkit River
and the Kanowit River.
Malaysia's largest and tallest (160m) hydro electric project, Bakun Hydro Electric Dam Project, is located on Batang Balui narrow Bakun Fall.
The biggest town by the river is Sibu
, some 60 kilometers upriver from the mouth of the Rajang. The next major settlement upriver is Kanowit
built on the mouth of Kanowit River at the bank of Rajang River, approximately 174 kilometers from the coast of South China Sea and about an hour boat ride from Sibu, followed by Kapit
as the last major town on the river. Others smaller towns are Song
and Belaga
.
epoch or Mesolithic
period about 10,000 years ago, there was a 5 degrees Celsius drop in the global temperature. At mountaintops, rainfall as snow and accumulated as huge icy sheets (including Mount Kinabalu
), thus making a break in the global hydrological cycle. Due to lack of water discharge into the sea, there was a 120-meter drop of sea levels from the present time. The South China Sea dried up, exposing the Sunda Shelf
and previous deep trenches became huge ancient rivers called the North Sunda River.
Asian Mainland, Malay Peninsular, Sumatra
and Java became connected to Borneo
via the landbridge of exposed Sunda Shelf. The North Sunda River provided vital connection to Mekong River in Vietnam and Chao Phraya River
in Thailand to the north, Baram
and Rajang rivers in Sarawak
to the east and Pahang River
and Rompin River
to the west of the massive land mass. Freshwater catfishes from those rivers migrated and mated to exchange their genetic materials about 10,000 years ago. Thus, after the Holocene
, when the temperature increased, the landbridges and Sunda River were inudated and the catfish populations were isolated. However, their genetic motives are still in the DNA
as an evidence of the previous connections of Rajang River to other isolated rivers in Indochina and Borneo.
on 8 October. The logjam have caused transportation difficulties for the people living along side the river and dead fish were also seen on the river.
Sarawak environment and public health minister, Datuk Seri Wong Soon Koh claimed that the logjam disaster had never happened before in such a large scale. However, land development minister, Datuk Seri James Masing claimed that similar incidents did happen before and he blamed the disaster on indiscriminate logging by irresponsible logging companies. The state's chief minister, Abdul Taib Mahmud
had advised the people of Sarawak not to accuse anyone for the causes of this logjam and he assured that the state government will probe into this matter. Movement for Change, Sarawak (MoCS) had proposed that a committee with equal representations from government and opposition should be established for identifying the exact cause of logjam in Rajang river.
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
, Malaysia. The river is located in northwest of Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
and it originates in the Iran Mountains. The river flows approximately 563 km to the South China Sea
South China Sea
The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around...
, making it the longest river in Malaysia.
The upper part of Rajang River is also known as Batang Balui by the Orang Ulu. Some of the more important tributaries are the Katibas River
Katibas River
Katibas River is a river in Sarawak state, Malaysia. It is a tributary of the Rajang River....
, the Balleh River
Balleh River
Balleh River is a river in Sarawak state, Malaysia. It is a tributary of the Rajang River....
, the Bangkit River
Bangkit River
The Bangkit River is a river in Sarawak state, Malaysia. It is a tributary of the Rajang River....
and the Kanowit River.
Malaysia's largest and tallest (160m) hydro electric project, Bakun Hydro Electric Dam Project, is located on Batang Balui narrow Bakun Fall.
The biggest town by the river is Sibu
Sibu, Sarawak
Sibu is an inland town, and the capital of Sibu District in Sibu Division, Sarawak, east Malaysia. It is located at the confluence of the Rajang and Igan Rivers, some 60 kilometres from the ocean and approximately east-north-east of the state capital Kuching...
, some 60 kilometers upriver from the mouth of the Rajang. The next major settlement upriver is Kanowit
Kanowit
Kanowit is a town and the capital of a district of the same name, located within the Sibu Division, Sarawak, east Malaysia, comprising 2,253.5 square kilometers. As of 2002, Kanowit's population is 28,600. It is built on the mouth of Kanowit River at the bank of Rajang River, approximately...
built on the mouth of Kanowit River at the bank of Rajang River, approximately 174 kilometers from the coast of South China Sea and about an hour boat ride from Sibu, followed by Kapit
Kapit
The town of Kapit is the capital of the Kapit District in the Kapit Division, Sarawak, east Malaysia on the south bank of the Rajang River. The district comprises 15,595.6 square kilometers and as of 2002 has a population of 60,200....
as the last major town on the river. Others smaller towns are Song
Song, Sarawak
Song is a town, and the capital of the Song District in Kapit Division, Sarawak, east Malaysia. The district population was 20,046. Song is situated by the banks of the Katibas River.-External links:*...
and Belaga
Belaga, Sarawak
Belaga is the capital of the Belaga District in the Kapit Division of Sarawak in east Malaysia. It is located on the upper reaches of the Rajang River, some 120 kilometers northeast of Kapit as the crow flies but considerably further on the river and slightly less than 100 kilometers...
.
Environmental history: tributary of the prehistoric Sunda River
During the PleistocenePleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
epoch or Mesolithic
Mesolithic
The Mesolithic is an archaeological concept used to refer to certain groups of archaeological cultures defined as falling between the Paleolithic and the Neolithic....
period about 10,000 years ago, there was a 5 degrees Celsius drop in the global temperature. At mountaintops, rainfall as snow and accumulated as huge icy sheets (including Mount Kinabalu
Mount Kinabalu
Mount Kinabalu is a prominent mountain on the island of Borneo in Southeast Asia. It is located in the East Malaysian state of Sabah and is protected as Kinabalu National Park, a World Heritage Site. Kinabalu is the tallest peak in Borneo's Crocker Range and is the tallest mountain in the Malay...
), thus making a break in the global hydrological cycle. Due to lack of water discharge into the sea, there was a 120-meter drop of sea levels from the present time. The South China Sea dried up, exposing the Sunda Shelf
Sunda Shelf
Geologically, the Sunda Shelf is a south east extension of the continental shelf of Southeast Asia. Major landmasses on the shelf include the Malay Peninsula, Sumatra, Borneo, Java, Madura, Bali and their surrounding smaller islands. It covers an area of approximately 1.85 million km2...
and previous deep trenches became huge ancient rivers called the North Sunda River.
Asian Mainland, Malay Peninsular, Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
and Java became connected to Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
via the landbridge of exposed Sunda Shelf. The North Sunda River provided vital connection to Mekong River in Vietnam and Chao Phraya River
Chao Phraya River
The Chao Phraya is a major river in Thailand, with its low alluvial plain forming the centre of the country. It runs through Bangkok, the capital city, and then empties into the Gulf of Thailand.-Etymology:...
in Thailand to the north, Baram
Baram River
The Baram river is a river in Sarawak, East Malaysia on the island of Borneo. The river originates in the central Iran Mountains and flows westwards through tropical rainforest to the South China Sea....
and Rajang rivers in Sarawak
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
to the east and Pahang River
Pahang River
Pahang River or is a river in the state of Pahang, Malaysia on the Malay Peninsula. With 459 km in length, it is the longest river on the Malay Peninsula...
and Rompin River
Rompin River
Rompin River is a river in the Malaysian state of Pahang. It flows through the southeastern part of Pahang before emptying into the South China Sea....
to the west of the massive land mass. Freshwater catfishes from those rivers migrated and mated to exchange their genetic materials about 10,000 years ago. Thus, after the Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...
, when the temperature increased, the landbridges and Sunda River were inudated and the catfish populations were isolated. However, their genetic motives are still in the DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
as an evidence of the previous connections of Rajang River to other isolated rivers in Indochina and Borneo.
Logjam disaster
On 6 October 2010, heavy rain in Putai and Nungun in upper Baleh is said to have caused a massive landslides that brought logs and debris down into the Baleh river, tributaries above Kapit, and then into the Rajang river. It was estimated that the volume of the logs and debris had exceeded 300, 000 m3. This logjam had also affected the Igan river. The log debris, stretching 50 km long, had reached SibuSibu
Sibu may refer to:*Sibu, Sarawak in Eastern Malaysia*Sibu Division*Sibu , an impact crater on Mars*Pulau Sibu, an island off the eastern coast of peninsular Malaysia*Sibu , name of a goddess in the Bribri tribe, in Costa Rica...
on 8 October. The logjam have caused transportation difficulties for the people living along side the river and dead fish were also seen on the river.
Sarawak environment and public health minister, Datuk Seri Wong Soon Koh claimed that the logjam disaster had never happened before in such a large scale. However, land development minister, Datuk Seri James Masing claimed that similar incidents did happen before and he blamed the disaster on indiscriminate logging by irresponsible logging companies. The state's chief minister, Abdul Taib Mahmud
Abdul Taib Mahmud
Pehin Sri Haji Abdul Taib bin Mahmud is the fourth and current Chief Minister of Sarawak. He is also the state Financial Minister and Planning and Resource Management Minister. Taib is the President of Parti Pesaka Bumiputera Bersatu , which is part of the Barisan Nasional coalition...
had advised the people of Sarawak not to accuse anyone for the causes of this logjam and he assured that the state government will probe into this matter. Movement for Change, Sarawak (MoCS) had proposed that a committee with equal representations from government and opposition should be established for identifying the exact cause of logjam in Rajang river.