Pansipit River

Pansipit River
River
Pansipit River under the Lemery, Batangas bridge
Country	Philippines
Region	Calabarzon
District	Batangas
Source	Taal Lake
- elevation	5 m (16 ft)
- coordinates	13°55′51.1″N 120°56′59.2″E / 13.930861°N 120.949778°E / 13.930861; 120.949778
Mouth	Balayan Bay
- location	Batangas
- elevation	0 m (0 ft)
- coordinates	13°52′16.1″N 120°54′50.5″E / 13.871139°N 120.914028°E / 13.871139; 120.914028Coordinates: 13°52′16.1″N 120°54′50.5″E / 13.871139°N 120.914028°E / 13.871139; 120.914028
Length	9 km (6 mi)
A satellite image of the Taal Lake (right) and Balayan Bay to the left of the photograph with the Pansipit River connecting the two bodies of water.

The Pansipit River is a short river located in the Batangas province of the Philippines. The river is the sole drainage outlet of Taal Lake, which empties to Balayan Bay. The river stretches about 9 kilometres (5.6 mi) passing along the towns of Agoncillo, Lemery, San Nicolas and Taal serving as border between the communities. It has a very narrow entrance from Taal Lake.

Before the eruptions of Taal Volcano in the 18th century, Pansipit was a navigable channel connecting Taal Lake to Balayan Bay. Sailing ships and Chinese junks freely entered Taal Lake to visit the town of Taal and other population centers along its shores. The water of the lake was then saline. In 1754, after the culmination of worst eruption of Taal Volcano had subsided, the mouth of the river was found blocked by volcanic material, eventually raising the level of the lake. A narrower Pansipit River eventually formed from the layer of ejecta from the volcano and a new course was created. The present source of the river on the lake is perhaps ¹⁄₂ kilometre (0.31 mi) north of the old entrance with the new channel joining the old channel about 1 to 2 kilometres (0.62 to 1.24 mi) down the river valley. The change in the elevation of the lake also prevented sea water from flowing into the lake thus turning it to freshwater, its marine life evolved and adapted to freshwater living.

As the river is the sole drainage outlet, the Pansipit shares many of the unique biota found in the lake. One specific strain, the lake's freshwater population of the jack Caranx ignobilis, is known to conduct its annual migration runs through the river. Commonly known as the "giant trevally" and locally as maliputo, this population is particularly notable for inhabiting the river's freshwater waters since the species itself is commonly associated with coral reefs. At one time, more than 80 different species of fish were found to inhabit the river's waters, either as a migratory channel or as a permanent residence. This included Taal Lake's now-extinct population of bull sharks (Carcharhinus leucas).