Cagayan River
Encyclopedia
The Cagayan River is the longest and largest river in the Philippine Archipelago
. It is located in the Cagayan Valley
region in northeastern part of Luzon
island and traverses the provinces
of Nueva Vizcaya
, Quirino
, Isabela
and Cagayan
.
of the Central Luzon
at an elevation of approximately 1,524 meters. The river flows north for some 505 kilometers to its mouth at the Babuyan Channel near the town of Aparri, Cagayan
. The river drops rapidly to 91 meters above sea level some 227 kilometers from the river mouth. Its principal tributaries are the Chico, Siffu, Mallig, Magat and Ilagan Rivers.
Magat River is the largest tributary with an estimated annual discharge of 9,808 million cubic meters. It lies in the southwestern portion of the basin, stretching approximately 150 kilometers from Nueva Vizcaya down to its confluence with Cagayan River about 55 kilometers from the river mouth.
Both Magat and Chico Rivers have extensive drainage areas which comprise about 1/3 of the whole basin.
The Ilagan River originates from the western slopes of the Sierra Madre and drains the eastern central portion of the Cagayan River basin with an estimated yearly discharge of 9,455 million cubic meters. It flows westward and joins the Cagayan River at Ilagan, Isabela
, 200 kilometers from the mouth.
The Siffu-Mallig system lies on the slope of the Central Cordillera
ranges flowing almost parallel to the Magat River. Marshes and swamps are found in some parts of its lower reaches.
Cagayan River and its tributaries have deposited sediments of Tertiary and Quaternary origin, mostly limestone sands and clays, throughout the relatively flat Cagayan Valley which is surrounded by the Cordillera Mountains
in the west, Sierra Madre
in the east and the Caraballo Mountains
in the south.
The river has a drainage area of about 27,300 km². in the provinces of Apayao, Aurora
, Cagayan, Ifugao, Isabela, Kalinga, Mountain Province
, Nueva Vizcaya, and Quirino.
The estimated annual discharge is 53,943 million cubic meters with a groundwater reserve of 47,895 million cubic meters.
season in Southeast Asia
from May to October.
The average annual rainfall in 1,000 mm in the northern part and 3,000 mm in the southern mountains where the river's headwaters lie. Water from the mountains flow down very slowly because of surface retention over the extensive flood plain, the gorges in the gently-sloping mountains and the meandering course of the river.
The inundation of the Cagayan River and its tributaries have caused great loss of life and property and substantial losses to the local and national economies. The Philippine government has established several flood warning stations along the river. Experts are specifically monitoring the lower reaches from Tuguegarao to Aparri and the alluvial plain from Ilagan to Tumauini, Isabela
.
It supports the lives of numerous endemic and endangered species, like the Luzon bleeding-heart pigeon (Gallicolumba luzonica), Philippine eagle (Pithecophaga jefferyi) and a rare riverine fish, locally called ludong (Cestreaus plicatilis
).
The ludong spawns in Cagayan River's upper reaches in Jones, Isabela
. In late October until mid-November, the fish travel down the river to release their eggs at the river mouth near Appari.
In February, ludong fry by the millions are again caught in fine nets as these travel upstream.
Due to the dwindling number of ludong caught yearly, local governments have imposed a ban on catching the fish and its fry, but the ban has failed.
, Quirino
, Isabela and Cagayan
. These provinces have an approximate population of two million people, mostly farmers and indigenous tribesmen.
The Ibanag people derive their tribe's name from Cagayan River's ancient name, Bannag. The Gaddang tribe lived in the upper riches of the Cagayan River and its tributaries.
There are dams in two of the river's tributaries, the Magat and Chico Rivers, and there are also several mining concessions in the mineral-rich Cordillera Mountains near the headwaters of the two tributary rivers.
The provincial governments along the river have also developed tourism programs that offer activities on the river, particularly whitewater rafting.
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
. It is located in the Cagayan Valley
Cagayan Valley
Cagayan Valley is a region of the Philippines, also designated as Region II or Region 02. It is composed of five provinces, namely: Batanes, Cagayan, Isabela, Nueva Vizcaya, and Quirino...
region in northeastern part of Luzon
Luzon
Luzon is the largest island in the Philippines. It is located in the northernmost region of the archipelago, and is also the name for one of the three primary island groups in the country centered on the Island of Luzon...
island and traverses the provinces
Provinces of the Philippines
The Provinces of the Philippines are the primary political and administrative divisions of the Philippines. There are 80 provinces at present, further subdivided into component cities and municipalities. The National Capital Region, as well as independent cities, are autonomous from any provincial...
of Nueva Vizcaya
Nueva Vizcaya
Nueva Vizcaya is a province of the Philippines located in the Cagayan Valley region in Luzon. Its capital is Bayombong. It is bordered by, clockwise from the north, Ifugao, Isabela, Quirino, Aurora, Nueva Ecija, Pangasinan, and Benguet.-History, people and culture:The name was derived from the...
, Quirino
Quirino
Quirino is a province of the Philippines located in the Cagayan Valley region in Luzon. Its capital is Cabarroguis and was named after Elpidio Quirino, the sixth President of the Philippines. The province borders Aurora to the southeast, Nueva Vizcaya to the west, and Isabela to the north...
, Isabela
Isabela province
Isabela is the second largest province of the Philippines next to Palawan. It is located in the Cagayan Valley Region in Luzon. Its capital is Ilagan and borders, clockwise from the south, Aurora, Quirino, Nueva Vizcaya, Ifugao, Mountain Province, Kalinga, and Cagayan...
and Cagayan
Cagayan
Cagayan , the "Land of Smiling Beauty", is a province of the Philippines in the Cagayan Valley region in Luzon. Its capital is Tuguegarao City and is located at the northeastern corner of the island of Luzon. Cagayan also includes the Babuyan Islands to the north. The province borders Ilocos Norte...
.
Topography
The river's headwaters are at the Caraballo MountainsCaraballo Mountains
Caraballo Mountains is a mountain range in the central part of Luzon, Philippines. It is located between Cordillera Central and Sierra Madre mountain ranges, at .This Caraballo Mountains are the location of the headwaters of the Cagayan River....
of the Central Luzon
Central Luzon
Central Luzon , also known as Region III , is an administrative division or region of the Republic of the Philippines, primarily serve to organize the 7 provinces of the vast central plain of the island of Luzon , for administrative convenience...
at an elevation of approximately 1,524 meters. The river flows north for some 505 kilometers to its mouth at the Babuyan Channel near the town of Aparri, Cagayan
Cagayan
Cagayan , the "Land of Smiling Beauty", is a province of the Philippines in the Cagayan Valley region in Luzon. Its capital is Tuguegarao City and is located at the northeastern corner of the island of Luzon. Cagayan also includes the Babuyan Islands to the north. The province borders Ilocos Norte...
. The river drops rapidly to 91 meters above sea level some 227 kilometers from the river mouth. Its principal tributaries are the Chico, Siffu, Mallig, Magat and Ilagan Rivers.
Magat River is the largest tributary with an estimated annual discharge of 9,808 million cubic meters. It lies in the southwestern portion of the basin, stretching approximately 150 kilometers from Nueva Vizcaya down to its confluence with Cagayan River about 55 kilometers from the river mouth.
Both Magat and Chico Rivers have extensive drainage areas which comprise about 1/3 of the whole basin.
The Ilagan River originates from the western slopes of the Sierra Madre and drains the eastern central portion of the Cagayan River basin with an estimated yearly discharge of 9,455 million cubic meters. It flows westward and joins the Cagayan River at Ilagan, Isabela
Ilagan, Isabela
Ilagan is a 1st-class municipality in the province of Isabela, Philippines. It is the capital municipality and the largest town of Isabela...
, 200 kilometers from the mouth.
The Siffu-Mallig system lies on the slope of the Central Cordillera
Cordillera Mountains
*Andes in South-America *Cordillera Central in the Philippines...
ranges flowing almost parallel to the Magat River. Marshes and swamps are found in some parts of its lower reaches.
Cagayan River and its tributaries have deposited sediments of Tertiary and Quaternary origin, mostly limestone sands and clays, throughout the relatively flat Cagayan Valley which is surrounded by the Cordillera Mountains
Cordillera Mountains
*Andes in South-America *Cordillera Central in the Philippines...
in the west, Sierra Madre
Sierra Madre (Philippines)
The Sierra Madre is a mountain range in The Philippines. It is located along the north-eastern coast of Luzon Island, running north/south. Quezon National Forest Park is situated in the range.-Geography:...
in the east and the Caraballo Mountains
Caraballo Mountains
Caraballo Mountains is a mountain range in the central part of Luzon, Philippines. It is located between Cordillera Central and Sierra Madre mountain ranges, at .This Caraballo Mountains are the location of the headwaters of the Cagayan River....
in the south.
The river has a drainage area of about 27,300 km². in the provinces of Apayao, Aurora
Aurora province
Aurora is a province of the Philippines located in the Central Luzon region. Its capital is Baler and borders, clockwise from the south, the provinces of Quezon, Bulacan, Nueva Ecija, Nueva Vizcaya, Quirino, and Isabela. To the east of Aurora is the Philippine Sea.Before 1979, Aurora was part of...
, Cagayan, Ifugao, Isabela, Kalinga, Mountain Province
Mountain Province
Mountain Province is a landlocked province of the Philippines in the Cordillera Administrative Region in Luzon. Its capital is Bontoc and borders, clockwise from the south, Ifugao, Benguet, Ilocos Sur, Abra, Kalinga, and Isabela.Mountain Province is sometimes incorrectly named Mountain in some...
, Nueva Vizcaya, and Quirino.
The estimated annual discharge is 53,943 million cubic meters with a groundwater reserve of 47,895 million cubic meters.
Flooding
The Cagayan River and its tributaries are subject to extensive flooding during the monsoonMonsoon
Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea...
season in Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
from May to October.
The average annual rainfall in 1,000 mm in the northern part and 3,000 mm in the southern mountains where the river's headwaters lie. Water from the mountains flow down very slowly because of surface retention over the extensive flood plain, the gorges in the gently-sloping mountains and the meandering course of the river.
The inundation of the Cagayan River and its tributaries have caused great loss of life and property and substantial losses to the local and national economies. The Philippine government has established several flood warning stations along the river. Experts are specifically monitoring the lower reaches from Tuguegarao to Aparri and the alluvial plain from Ilagan to Tumauini, Isabela
Tumauini, Isabela
Tumauini is now a 1st class municipality in the province of Isabela, Philippines. According to the latest census, it has a population of 55,041 people in 9,239 households....
.
Flora and fauna
The Cagayan River passes through one of the few remaining primary forests in the Philippines.It supports the lives of numerous endemic and endangered species, like the Luzon bleeding-heart pigeon (Gallicolumba luzonica), Philippine eagle (Pithecophaga jefferyi) and a rare riverine fish, locally called ludong (Cestreaus plicatilis
Lobed river mullet
The Ludong or Lobed river mullet is a freshwater mullet that is endemic to Cagayan River and tributaries extending through the watersheds of Cagayan Valley and the Santa-Abra River Systems of Ilocos Sur and Abra in the Philippines...
).
The ludong spawns in Cagayan River's upper reaches in Jones, Isabela
Jones, Isabela
Jones is a 2nd class municipality in the province of Isabela, Philippines. According to the latest census, it has a population of 41,237 people in 8,171 households.-History:...
. In late October until mid-November, the fish travel down the river to release their eggs at the river mouth near Appari.
In February, ludong fry by the millions are again caught in fine nets as these travel upstream.
Due to the dwindling number of ludong caught yearly, local governments have imposed a ban on catching the fish and its fry, but the ban has failed.
People
The river traverses four provinces: Nueva VizcayaNueva Vizcaya
Nueva Vizcaya is a province of the Philippines located in the Cagayan Valley region in Luzon. Its capital is Bayombong. It is bordered by, clockwise from the north, Ifugao, Isabela, Quirino, Aurora, Nueva Ecija, Pangasinan, and Benguet.-History, people and culture:The name was derived from the...
, Quirino
Quirino
Quirino is a province of the Philippines located in the Cagayan Valley region in Luzon. Its capital is Cabarroguis and was named after Elpidio Quirino, the sixth President of the Philippines. The province borders Aurora to the southeast, Nueva Vizcaya to the west, and Isabela to the north...
, Isabela and Cagayan
Cagayan
Cagayan , the "Land of Smiling Beauty", is a province of the Philippines in the Cagayan Valley region in Luzon. Its capital is Tuguegarao City and is located at the northeastern corner of the island of Luzon. Cagayan also includes the Babuyan Islands to the north. The province borders Ilocos Norte...
. These provinces have an approximate population of two million people, mostly farmers and indigenous tribesmen.
The Ibanag people derive their tribe's name from Cagayan River's ancient name, Bannag. The Gaddang tribe lived in the upper riches of the Cagayan River and its tributaries.
Economic importance
The river drains a fertile valley that produces a variety of crops, including rice, corn, bananas, coconut, citrus and tobacco.There are dams in two of the river's tributaries, the Magat and Chico Rivers, and there are also several mining concessions in the mineral-rich Cordillera Mountains near the headwaters of the two tributary rivers.
The provincial governments along the river have also developed tourism programs that offer activities on the river, particularly whitewater rafting.