Here are the 10 longest rivers in the Philippine archipelago.
5.) Pampanga River – 260 km
Pampanga River, which is formerly known as Rio Grande de Pampanga or Great River of Pampanga, is the Philippines 2nd largest river. Pampanga River‘s headwaters are located at the Sierra Madre and has a total length of 260 km and has a river’s basin that covers an area of 10,540 km².
6.) Agno River – 206 km
The Agno River in Pangasinan province is the country’s 5th largest river system and has a drainage area of 5,952 km². This wonderful river is the main drainage system of the area and its catchment base is 5,952 km². This river is also Luzon’s third largest river and Philippines’ 5th largest river in the country. Likewise, Agno River is the largest Philippine river in terms of water discharge, draining around 6.6 cubic kilometers of fresh water into Lingayen Gulf. It has a length of 206 km.
7.) Abra River – 178 km
The longest rivers in the country are mostly located in the island of Luzon. Abra River is the Philippines 6th largest river system in terms of watershed size. It has an estimated drainage area of 5,125 square kilometers and a length of 178 kilometers from its source in the vicinity of Mount Data in the province of Benguet.
8.) Abulog River – 175 km
Abulog River is the Philippines’ 9th largest river system in terms of watershed size and has an estimated drainage area of 3,372 km². As one of the country’s longest rivers, it has a total length of 175 kilometers. Its source started in the mountains of Kalinga in the Cordillera Administrative Region. Over 90% of the drainage area of Abulog River is located in the province of Kalinga and the remainder is in the province of Cagayan.
9.) Chico River – 174.7 km
Chico River in the province of Kalinga in Cordillera Autonomous Region is one of the smallest provinces in the Philippines. This river system in Kalinga province, which is a landlocked province of CAR, is one of the country’s longest rivers. Chico River has a total length of 174.67 kilometers.
10.) Davao River – 160 km
Davao River is one of the longest rivers in the Philippines. It has a total length of 160 km and its catchment is Mindanao’s third largest. Davao River drains an area of over 1,700 km² and the area seldom experiences typhoons.
Other notable rivers…
*Bicol River – 94 km
Bicol River is the 8th largest in terms of drainage basin with a catchment area of 3,770 km². It terms of length, it is one of the longest rivers in the country. It passes through the provinces of Albay, Camarines Norte and Camarines Sur. It has a length of 94 km.
Marikina River or Ilog Marikina in Metro Manila is a main river system that stretches from Rodriguez, Rizal to Pasig City. During the Spanish regime, the river served as an important transport route. It became polluted due to negligence and industrial development. The river was transform into one of the most important treasures of the City of Marikina in the late 1990s. Marikina River is recognized as Hall of Famer for the Cleanest Inland Water in Metro Manila.
Another notable river in the country is the Calumpang River or Ilog Calumpang in the province of Batangas. It has a catchment area of about 472 km². Recent study shows that the river is now highly contaminated putting some shrimp and fish species in danger of extinction.