1. Laguna de Bay
SURFACE AREA: 90,000 – 94,900 hectares (900 – 949 kilometers2) or 222,395 – 234,503 acres (348 – 366 miles2)
MAXIMUM DEPTH: 20 meters (66 feet)
SURFACE ELEVATION: 2 meters (7 feet) above sea level
LOCATION: Laguna, Rizal, Metro Manila
On the southern part of the massive island of Luzon in the Philippines, between the provinces of Laguna and Rizal and the cities of Metropolitan Manila lies a gigantic and sprawling freshwater lake not unlike a sea itself, albeit an inland one. This lake is known as Laguna de Bay, and it is by far the largest lake anywhere in the Philippines, covering a vast surface area of about 90,000 to 94,900 ha (222,395 to 234,503 ac) – almost three times as large as the country’s next biggest lake (Lake Lanao)! The name of the lake is Spanish for ‘Lagoon of Bay’, with Bay being an ancient pre-colonial town – now a modern-day municipality – built along the southern shoreline of the lake and that once served, for some time, as the capital of Laguna province during the Spanish colonial era.
For so broad an inland body of water, Laguna de Bay is surprisingly very shallow – it only has an average depth of around 2.5 m (8 ft) and reaches a maximum depth of 20 m (66 ft) at the Diablo Pass. It occupies a vast basin shaped akin to a three-pronged dinosaur footprint, or a stylized ‘W’, with two peninsulas extending from the northern shoreline dividing the northern half of the lake into three bays: the West Bay, Central Bay, and East Bay (some recognize a fourth bay, the South Bay along the southern shoreline). The Central Bay actually fills the Laguna Caldera, a volcanic crater believed to have been formed about a million years ago. A number of islands dot the wide lacustrine surface: the largest of these is Talim Island, an elongated and densely-populated isle situated at the tip of the peninsula closer to the western coast, separated only by a hair’s breadth of water (the Diablo Pass).
Along the northwestern shoreline of Laguna de Bay are clustered the crowded and populous cities of Metro Manila, which thoroughly cover a narrow belt of land bounded by the lake on one side and Manila Bay on the other. To the north of the lake are low-lying plains encompassing cultivated fields and farmlands, as well as swaths of grassland and brushland, between which are built numerous well-peopled settlements that belong to the municipalities of Rizal province. Beyond them are the long rows and ranks of mountains of the Sierra Madre. To the east, south, and west are the lakeshore cities and municipalities of Laguna province (among which is Bay), spread out over a vast and level landscape of rice paddies, coconut plantations, and wide tracts of cropland. Over this countryside terrain looms large mountains: to the east tower the peaks of the Sierra Madre as they continue their march southwards along the eastern coast of Luzon; while to the south stands the massive and imposing figure of Mount Makiling (1,090 m or 3,576 ft ASL), a mountain steeped in legend, overlooking the broad, blue expanse of the lake from its lofty seat at the southern shoreline. Further south, beyond Makiling, Mount Banahaw (2,170 m or 7,119 ft ASL) and the Malepunyo Mountain Range (otherwise known as the Malarayat Mountain Range) lord over the plain.
It is believed that Laguna de Bay was once part of Manila Bay, or an ’arm of the sea’. The lake is fed by as many as 100 influents, with 21 of these being major tributary rivers, such as the Bumbungan River (more popularly referred to as the Pagsanjan River), which spills into the lake from the east and accounts for as much as 18 – 20% of the total water inflow to the lake; the Santa Cruz River; and the Marikina River, among others. The lake has one lone outlet, the Pasig River, which drains the lake from its northwestern shore and thence courses northwestward to empty into Manila Bay. However, when the water level of the lake drops below that of Manila Bay (a common occurrence, particularly after the dry season, as Laguna de Bay’s normal surface elevation is only less than 2 m or 7 ft ASL), the Pasig River becomes a tributary instead, backflowing and bringing seawater lakeward, and rendering parts of the otherwise freshwater lake brackish.
Laguna de Bay is not only the Philippines’ largest lake; it is also arguably the most important inland body of water anywhere in the country. The lake is especially crucial to the economic development of the wide region surrounding it, providing a variety of benefits to the lakeshore communities. First and foremost, Laguna de Bay serves as one of the country’s primary sources of commercially important freshwater fish (and prawns), which are harvested through open-water fishing and through aquaculture. Second, the lake is used as a source of animal feed (notably snails and mollusks) for the thriving duck industry hosted in the lakeside settlements. Third, the lake (along with its tributaries) supplies water for irrigation, power, and household and industrial use (such as for cooling industrial equipment). Moreover, the lake functions as a waterway for the transportation of passengers and cargo between the surrounding communities, as well as a temporary reservoir for floodwaters coming from Metro Manila and even as an effluent sink. The lake also holds potential for tourism and recreation if its degradation is reversed.
2. Lake Lanao
SURFACE AREA: 36,300 ha (363 km2) or 89,699 ac (140 mi2)
MAXIMUM DEPTH: 112 m (368 ft)
SURFACE ELEVATION: 700 m (2,297 ft) ASL
LOCATION: Lanao del Sur
Deep in the heart of the province of Lanao del Sur, in the island of Mindanao on the southern reaches of the Philippines, there lies a lake of immense breadth, ancient age, and paramount economic, social, historical, and cultural importance. Lake Lanao, it is called, a veritable landlocked sea set in the midst of a panorama of rolling hills and wild hinterland, green vales and forested valleys, and rich fields and fertile farmlands. Half of this lake is walled by a ragged ring of mountains: to the southeast, by the Piapayungan Mountain Range, whose secluded and vastly unmapped peaks are among the country’s highest mountains; to the south, by the scattered and sprawling mass of lofty hills and heights known as the Butig Mountains, which extends east to meet the higher Piapayungan Range; and to the southwest and west, by Mount Inayawan (1,535 m or 5,036 ft ASL) and the many smaller mountains marshalled about it (together known as the Inayawan Mountain Range).
Lake Lanao is a very old lake; it is reckoned to be more than 2 million years old. In fact, it is accounted among the ancient lakes of the world, or the lakes that have existed for more than a million years. And it is particularly vast: with a surface area of 36,300 ha (89,699 ac), Lake Lanao is the largest lake in Mindanao and the second largest lake in the Philippines. It is quite deep, too: the lakewaters are shallower on the northern half, but plumbs continuously deeper towards the south, eventually reaching a maximum depth of 112 m (368 ft). A considerably lofty surface elevation of 700 m (2,297 ft) ASL renders the local climate sufficiently mild.
Five forested watersheds ranged all around the shoreline of Lake Lanao and beyond supply the lake its water, which is conveyed primarily through five major tributary rivers, namely the Ramain, Taraka, Gata, Masiu and Bacayawan Rivers. The lake is drained by only one outlet – the Agus River, which flows northwestward, through well-tilled fields and well-peopled settlements and down through wooded slopes and newly-forested uplands, before splitting into two channels, with one channel cascading over the Maria Cristina Falls and the other over the Tinago Falls, two waterfalls of great height and wondrous natural beauty, until both channels reach at last the saline expanse of Iligan Bay and there deliver their freshwater freightage.
The ancient Lake Lanao has long cradled life, from the floral and faunal species that have flourished around it and within its watery depths, of which a number are found nowhere else in the world; to the people who have built a lasting and remarkable civilization along its banks. For Lake Lanao is the home of the Maranaos (Meranaos), literally the ‘People of the Lake’ (Ranao is the Maranao word for ‘lake’, and Lanao is merely an alteration of the original), and by the lakeshore they have founded their settlements and raised their grand mosques and resplendent torogans (the traditional homes of their sultans and datus, their lords). The bountiful waters of the lake they have fished; its rich depths they have plumbed; and its vast, blue surface they plied in awangs, their traditional outrigger boats with richly carved and painted prows and sterns. The fertile lands along the coast they have tilled, and in the encompassing forests and mountains they have foraged and hunted. Here they have lived, and here they have flourished, enduring through the long count of years, valiantly defying the intrusions and invasions of foreign forces who came to conquer. In much the same way as their torogan, sarimanok (a legendary bird of the Maranao), and singkil (a Maranao folk dance) are, Lake Lanao is woven into their Darangen (a Maranao epic poem), into their lore and legends, into their tales and myths, and indeed into their colorful history and very identity.
Today, Lake Lanao is no less significant. In fact, if anything, the second largest lake in the Philippines has only become more important not only to the Maranaos, but to the rest of the peoples of Mindanao. Apart from providing food and water for irrigation and domestic use to the dwellers of Marawi City on the northern lakeside and the many other towns encircling the lake; and facilitating transport between those communities, the hydroelectric plant installed along the lake and its sole outlet, the Agus River, generates 70% of the electricity used by the people of Mindanao.
3. Taal Lake
SURFACE AREA: 23,420 ha (234 km2) or 57,872 ac (90 mi2)
MAXIMUM DEPTH: 172 m (564 ft)
SURFACE ELEVATION: 5 m (16 ft) ASL
On the northern bounds of the province of Batangas in Luzon, a short distance to the southeast of Laguna de Bay lies yet another one of the Philippines’ largest lakes – Taal Lake. Though not as vast or immense as its gigantic lacustrine neighbor to the north, Taal Lake is still a massive lake on its own. Encompassing a surface area of 23,420 ha (57,872 ac), Taal Lake is the second largest lake in Luzon, and the third largest throughout the Philippines. The depths of this freshwater volcanic crater lake range from a mean 100 m (328 ft) to as far down below the surface as 172 m (564 ft).
Taal Lake occupies the greater part of the Taal Caldera of Taal Volcano (311 m or 1020 ft ASL), an ancient caldera believed to have been formed hundreds of thousands of years ago. The lake is walled to the north and northwest by the Tagaytay Ridge, a long and lofty tableland that is actually the northern rim of the Taal Caldera. The ridge has a broad and relatively level top, but upon much of its lakeward face are steep cliffs and precipitous escarpments that drop sharply towards the lake waters. To the south and southwest, the lake is bounded by a fence of high cliffs which culminates in Mount Macolod (947 m or 3,107 ft ASL), known to some as Mount Maculot, the highest point of the caldera rim that is positioned directly opposite the Tagaytay Ridge. The lake is fed by some 37 tributaries, and its solitary outflow is the Pansipit River, which drains the lake from a breach in the southwestern cliffs, and thence flows southwestward to discharge its waters at Balayan Bay.
Across the broad surface of Taal Lake are scattered a number of islands. The largest of these is Volcano Island, which lies close to the center of the lake. Within Volcano Island is a small lake known as the Main Crater Lake or Yellow Lake, and within this lake, a tiny islet known as Vulcan Point. Volcano Island is the site of Taal Volcano’s historical eruptions, which, since records began in 1572, have numbered at least 34 times, with the most recent one occurring in January 2020. For such a low volcano, Taal is unbelievably violent: it is regarded as one of the world’s lowest but deadliest volcanoes, responsible for some of the largest and most fatal eruptions in the Philippines. It is the smallest active volcano in the world, and is the second most active volcano in the Philippines (next to Mount Mayon in Albay).
Indeed, it is on account of Taal Volcano’s destructive explosions that Taal Lake is a freshwater lake. Prior to the volcano’s eruptions in the 18th century, Taal Lake was filled with saline waters, as it was but an inlet of Balayan Bay, connected to the sea via the Pansipit River, which then was wider and was navigable, and along it ships freely sailed to and fro the lakeside settlements. But the volcano’s particularly devastating eruption in 1754, which is said to have lasted some 200 days and is regarded as Taal Volcano’s greatest and most ruinous eruption to date, discharged such an amount of ejecta that the Pansipit River was almost wholly blocked, preventing seawater from flowing in and causing the water level of the lake to rise, which submerged the surrounding coastal settlements. Centuries of rainfall turned the erstwhile saline lake waters fresh, and continued to raise the water level up to its modern-day surface elevation of 5 m (16 ft) ASL.
Despite the ever-present and fatal threat posed by the volcano, Taal Lake and its environs miraculously abound with life. Along the coast of the lake are numerous settlements with numerous people, bustling with activity and industry, while the lake itself hosts an exceedingly remarkable collection of faunal species. The lake’s transition from saltwater to freshwater has produced some of the most unique animals not found elsewhere in the globe, such as the maliputo, or freshwater trevally; the tawilis, or freshwater sardine (Sardinella tawilis), the only one of its kind in the world; the gobies Gnatholepis volcanus and Rhinogobius flavoventris; and the duhol, or the Lake Taal snake (Hydrophis semperi), one of the only two species of freshwater sea snakes in the world. Taal Lake forms the core of the Taal Volcano Protected Landscape, an area encompassing the lake, volcano, and their surrounds; and by all intents and purposes a National Park, home to a multitude of bird, fish, and reptile species.
Owing to their iconic and inimitable beauty and scenery, especially when beheld from Tagaytay City upon the Tagaytay Ridge, Taal Lake and Volcano rank among the country’s most popular tourist draws. Before the volcano’s 2020 eruption, tours of the third largest lake in the Philippines, and of Volcano Island, were offered; and tourists could hike through scenic trails towards the Main Crater Lake.
4. Lake Mainit
SURFACE AREA: 17,340 ha (173 km2) or 42,848 ac (67 mi2)
MAXIMUM DEPTH: 223 m (732 ft)
SURFACE ELEVATION: 42 m (138 ft) ASL
LOCATION: Surigao del Norte, Agusan del Norte
Lake Mainit is an enormous inland body of freshwater situated on the northeastern tip of the island of Mindanao, on the border of Surigao del Norte and Agusan del Norte, divided almost equally between the provinces. The lake is separated from Butuan Bay and the vast Bohol Sea to the west only by a narrow strip of land, upon which runs the rugged ridge of forested mountains and hills known as the Malimono Range, forming a veritable fence on the lake’s western and northern shoreline. Eastwards and southwards of the lake are small sweeps and stretches of rice paddies, corn fields, coconut groves, and banana plantations. Beyond these, the lofty peaks of the Diwata Mountains, an extensive mountain range trending parallel to Mindanao’s eastern coast, loom large as they begin their long march south, from Surigao del Norte all the way to the Davao Region.
Lake Mainit, which is shaped akin to an elongated and inverted teardrop (though some say a pear), is fed by as many as 28 tributary creeks, streams, and rivers, but it has only one outflow – the Kalinawan River, which drains into Butuan Bay. The surface area of the lake measures 17,340 ha (42,848 ac), making it the second largest lake in Mindanao, and the fourth largest lake in the Philippines. But apart from figuring among the biggest, Lake Mainit is also reckoned as the deepest lake anywhere in the country: its waters plumb to a maximum depth of 223 m (732 ft). The name of the lake is a local word for ‘hot’, perhaps a reference to the lake’s rather warm waters, whose surface temperatures range from 27˚C to 30˚C (81°F to 86°F).
Arrayed all along the coasts of Lake Mainit are numerous fishing barangays (villages), for the lake is an important – perhaps the most important – source of food and livelihood to a great part of the local populace. The dominant fish species in the lake is the pijanga, or the white goby (Glossogobius giuris), though the lake also supports large stocks of other commercially important fishes such as the gourami (Gourami belontiidae), mudfish (Channa striata), common carp (Cyprinus carpio), and tilapia (Oreochromis niloticus); as well as some numbers of the once-abundant giant mottled eel (Anguilla marmorata), locally known kasili.
But apart from its diverse and teeming fish life, Lake Mainit is also home to numerous other plant and animal species, as it supports what is considered one of the more remarkable and important ecosystems in the Philippines. The forests that mantle the encircling mountains are the realms of trees of exceptional size, stature, significance, and rarity, and among these are the narra or Philippine mahogany (Pterocarpus indicus); molave (Vitex parviflora); toog or Philippine rosewood (Petersianthus quadrialatus); kamagong (Diospyros discolor); mangkono or Philippine ironwood (Xanthostemon verdugonianus); and the malabayabas or Philippine teak (Tristaniopsis decorticata). In these green woods and jungles, monkeys and wild boars are found. In the wetlands that fringe the shoreline, there flourish luxuriant layers of water hyacinths and lotuses, through which wild ducks are sometimes seen. Above and around the lake, the Mindanao scops owl (Otus mirus), white-bellied sea eagle (Haliaeetus leucogaster), and the savannah nightjar (Caprimulgus affinis), as well as forest kingfishers, among other remarkable birds, are occasional sights.
Lake Mainit is slowly emerging as a tourist spot in Mindanao, with fishing, boating and kayaking across the lake, and even birdwatching being some of the popular activities to indulge in in the area. The lake’s waters have remained mostly clean and clear, lending further appeal to what is already considered as one of the most scenic lakes in the Philippines. Moreover, through the countryside plains on the southern and eastern shorelines of the lake runs a section of the Pan-Philippine Highway, the country’s longest highway, and all who pass by this great road are feted with picturesque views of the deepest and fourth largest lake in the Philippines.
5. Naujan Lake
SURFACE AREA: 8,125 ha (81 km2) or 20,077 ac (31 mi2)
MAXIMUM DEPTH: 45 m (148 ft)
SURFACE ELEVATION: 20 m (66 ft) ASL
LOCATION: Oriental Mindoro
On the vast plains sprawled along the northeastern coast of the island of Mindoro, in the province of Oriental Mindoro sits Naujan Lake, an expansive freshwater lake shaped akin to a kidney. With an impressive surface area of 8,125 ha (20,077 ac), Naujan Lake forms the largest lake in Mindoro, the third largest in Luzon, and the fifth largest across the Philippines. At its deepest point, the lake reaches 45 m (148 ft) below the surface.
To the north and east, Naujan Lake is separated from the deep waters of Tayabas Bay and the Tablas Strait by a strip of coastal land only a few kilometers wide at its narrowest point. This veritable partition between the saltwater and the fresh is occupied by the Naujan Mountains, a line of mountains and hills of considerable elevation, whose highest point and peak, Mount Naujan (420 m or 1,378 ft ASL), stands in stark relief on the northern shoreline of the lake. West of Naujan Lake is a vast and open plain, the widest level ground anywhere in mountainous Mindoro, encompassing broad tracts of rice paddy fields, orchards, and, nearer to the lakeshore, pockets of fringing peatlands and marshlands. South of the lake are built-up and cultivated areas upon flat ground, beyond which the terrain eventually climbs into the mass of steep foothills and towering peaks that make up the Mindoro Mountain Range, the mountainous core of the island of Mindoro.
It is from the mountains to its north, east, and south that Naujan Lake accumulates much of its waters, though it is also fed from the west by a number of tributaries. From the rain-washed slopes of the Naujan Mountains in the east issue forth the Malayas, Malabo, Maambog, Malbog, and Cusay Creeks to deliver their waters to the lake. From the forested Mindoro Range to the south flow the Subaan and Singulan Rivers, wending their way north, bound for the lake. From the west, the Bambang, Tigbao, and Tagbakin Creeks also course lakewards to swell its waters. Naujan Lake has only one outlet – the Butas River (otherwise known as Naujan River), which empties into Tayabas Bay and the Tablas Strait.
Naujan Lake forms the focal point of the Naujan Lake National Park, a vast protected area encompassing a diverse assemblage of ecosystems, such as forest, grassland, marshland, and freshwater ecosystems; and home to an especially rich biodiversity, which includes 443 indigenous and 74 native species of trees and plants, 105 bird species, 21 mammal species, 33 reptile and amphibian species, and 30 fish species. Because of its international importance as a wetland site, Naujan Lake has been designated as a Ramsar Site.
Among the more notable fauna of the lake and its surround are the Philippine hawk-eagle (Nisaetus philippensis), Philippine duck (Anas luzonica), Mindoro imperial pigeon (Ducula mindorensis), Mindoro bleeding-heart (Gallicolumba platenae), black-hooded coucal (Centropus steerii), Mindoro hornbill (Penelopides mindorensis), ashy thrush (Geokichla cinerea), plain swamphen (Amaurornis olivaceous), Philippine freshwater crocodile (Crocodylus mindorensis), Philippine sailfin lizard (Hydrosaurus pustulatus), and the Mindoro variable-backed frog (Pulchrana mangyanum). Naujan Lake in particular is a vast and vital feeding and breeding place of numerous waterfowls and marsh birds, playing host to globally significant populations of migratory birds such as tufted ducks, terns, herons, egrets, bitterns, rails, and stilts; as well as migratory fishes.
Apart from its staggering ecological importance, the economic significance of the fifth largest lake in the Philippines is undeniable. Along the lakeside are gathered many communities that rely on the lake and its watershed not only for food and livelihood, but also for raw water supply for irrigation, hydro-power, and domestic use. The lake also facilitates transportation, easing the movement of people, products, and possessions to and fro the encircling lakeside communities, a faster and more preferable route rather than the lengthy transit overland.
Owing to its rich ecological treasures and scenic natural beauty, the Naujan Lake National Park is open for leisure travel and ecotourism, offering a range of recreational activities, such as picnics, boating, and birdwatching. The lake is also a highly sought-after destination for educational tours and scientific research.