World Lake Day

Lake topography , or bathymetry , refers to the underwater contour and physical shape of a lake bed. The Key Features of Lake Topography are Contour Lines: Lines on a map that connect points of equal depth. Close lines mean a steep drop-off; wide lines mean a flat bottom. Points: Tongues of land or underwater ridges extending from the shore into the lake. Humps: Raised areas or underwater islands rising from the lake floor. Saddles: Lower, depressed pathways or troughs situated between two separate humps or high spots. Channels: Original river or creek beds submerged when a reservoir or lake formed, usually marking the deepest path. Flats: Broad, shallow, and level areas where depth changes very slowly Some Tools for Mapping Lake Topography include: Navionics Chart Viewer: A popular digital mapping tool providing detailed depth contours and underwater terrain data. i-Boating Navigation App: Offers electronic navigational and fishing charts with bathymetric details. US Topo Maps : Pro...

  The highest commercially navigable lake in the world. In the central part of the Andes, on the borders of Peru and Bolivia, there Ües at an altitude near 3800 m an inland drainage plateau known as the Altiplano. The Lake Titicaca constitutes a freshwater resource for approximately 2.5-3.0 million persons residing in. Peru and Bolivia. The Lake Titicaca is the highest commercially navigable lake in the world, sitting at an altitude of approximately 3,810 meters (12,500 feet) in the Andes on the border of Peru and Bolivia. Surface Area: About 8,400 square kilometers (3,240 square miles). Depth: Reaches a maximum depth of 288 meters (945 feet) with a mean depth of around 135 to 139 meters. Volume: Approximately 930 cubic kilometers. Divisions: Split into two main sub-basins, Lago Mayor (the larger northern body) and Lago Menor (the smaller southern body), connected by the Tiquina Strait.

  The world's longest freshwater lake. East African Lake Tanganyika is probably best known among biologists for its speciose and highly diverse flock of cichlid fishes.  The Lake Tanganyika is an ancient African Great Lake and the longest freshwater lake in the world , stretching approximately 673 kilometers (418 miles) north-to-south. Located in the Western Rift Valley of East Africa, it holds roughly 17% of the world’s unfrozen surface fresh water and is shared by four countries: Tanzania (46%), the Democratic Republic of the Congo (40%), Burundi, and Zambia. Massive Biodiversity: It is a global hub for evolution. The lake houses over 2,000 species of plants and animals, including more than 250 species of colorful cichlid fish, 98% of which are completely endemic (found nowhere else on Earth). Anoxic Depths: Because of its extreme depth and lack of seasonal temperature mixing (a trait known as being a meromictic lake), there is no oxygen below roughly 200 meters. This creat...

  The Dead Sea is a landlocked salt lake bordered by Israel and the West Bank to the west and Jordan to the east, sitting at the lowest elevation on Earth at over 430 meters (1,400 feet) below sea level. Lowest Point: The shoreline is the lowest dry land on Earth. High Salinity: It is nearly 10 times saltier than the ocean, which makes it impossible to sink and allows people to easily float. Name Origin: High salt levels prevent fish, plants, and other life from growing, hence the name "Dead" Sea.

  About the world's largest saltwater lake . The Caspian Sea is the world's largest saltwater lake (and largest inland body of water), and it is bordered by Kazakhstan along its northeastern and eastern shore The Caspian Sea is the largest saltwater lake in the world by both surface area and volume. Surface Area: About 371,000 square kilometers (143,200 square miles). Maximum Depth: 1,025 meters (3,360 feet). Bordering Countries: Russia, Kazakhstan, Turkmenistan, Iran, and Azerbaijan. Salinity: It is brackish in the north near river inflows and saltier in the south.

Covering roughly 9,500 square kilometers (3,668 square miles) when full. The lake is Located in South Australia, about 700 kilometers north of Adelaide. The Kati Thanda-Lake Eyre is the largest lake in Australia in its dry state and a vast shallow inland sea when it fills with water after significant rainfall. When full it attracts millions of waterbirds within weeks as a vast ecological event unfolds across the remote outback. Scenic flights over Lake Eyre from William Creek or Marree provide the finest view of the extraordinary lake. Type: Ephemeral salt lake (usually a dry salt crust). The lake Sits 15 meters below sea level, making it the lowest natural point in Australia. The lake eyre Fills completely only a few times a century after heavy outback rains .

The largest lake in Russia by volume and depth is Lake Baikal in Siberia, while the Caspian Sea is the largest by surface area. The Lake Baikal. Located in Southern Siberia, between Irkutsk Oblast and the Republic of Buryatia, its Depth Reaches a maximum depth of 1,642 meters (5,387 feet), making it the deepest lake on Earth . The Lake Baikal Holds about 20% of the world's unfrozen surface freshwater , more than all the North American Great Lakes combined. The Age of the lake is estimated at 25 to 30 million years, making it the oldest major lake in geological history .

Collective action and sustainable practices are essential to preserve these vital water bodies for future generations and biodiversity.  

Recognizing the critical importance and compounding crises faced by lakes, a special event to commemorate World Lake Day is being organized to elevate the global political and technical profile of sustainable lake management. Lakes and reservoirs contain more than 90% of the world's liquid surface freshwater. They are the lifeblood of ecosystems, driving local economies, securing food and drinking water for billions, and regulating local climates. Despite their critical importance, lakes globally face unprecedented threats from pollution, agricultural runoff, climate-induced evaporation, and rapid biodiversity loss. Related Sites and Documents:  Draft Concept Note  &  Website . Watch Commemorating World Lake Day: Strengthening Global Cooperation for Sustainable Lake Management! Meetings & Events

  Lakes are vital natural resources that hold a large share of the world's surface freshwater and support life on Earth. Why Lakes Matter? Freshwater Supply : Lakes store clean water for drinking, farming (irrigation), and industrial use. Wildlife Homes: They provide habitats for many species of fish, plants, birds, and amphibians. Flood Control : Lakes absorb and hold extra stormwater during heavy rains to protect nearby land. Climate Control : They help moderate local temperatures and cool the surrounding air. Local Economy : Lakes offer spots for fishing, boating, and tourism that support nearby towns.

  The largest freshwater lake in the world by surface area and the coldest and deepest of the North American Great Lakes. The Lake Superior  region is a part of the southern margin of the great pre-Cambrian shield of northern North America.   The Surface Area is about 31,700 square miles (82,170 square kilometers); With a Max Depth of 1,332 feet (406 meters) and an Average Depth of 483 feet (147 meters). The Shoreline Length is About 1,826 miles bordering Ontario (Canada), Minnesota (US), Wisconsin (US), and Michigan (US). Water Volume: Holds 10% of the earth's fresh surface water—as much water as all the other Great Lakes combined plus three extra Lake Eries . Islands: Features Isle Royale (a large wilderness island) and the Apostle Islands, known for carved sea caves. Ecosystem: Home to 78 fish species, including lake trout, whitefish, and walleye. Shipwrecks: Contains over 350 recorded shipwrecks due to fierce storms on the open-water-like lake

   The largest lake in China. The Qinghai Lake is located on the northeastern part of the Tibetan Plateau in Qinghai Province. The lake Covers a surface area of about 4,300 to 4,500 square kilometers and Sits at roughly 3,200 meters (10,500 feet) above sea level. Type: An alkaline, endorheic (closed-basin) salt lake. Name: Historically known as Kokonor (meaning "Blue Sea" in Mongolian). Water Source: Fed by over 20 rivers and streams. Ecosystem: Serves as a major breeding ground for migratory birds and supports rare species like Przewalski's gazelle. Cultural Significance: Considered a sacred site by Tibetan Buddhists and local nomadic groups .

  The world's highest freshwater lake. T he Mapam Yumtso , also known as Lake Manasarovar , is a high-altitude freshwater lake located in Burang County, Ngari Prefecture, in the Tibet Autonomous Region of China. The lake sits at approximately 4,590 meters (15,060 feet) above sea level and is situated near the sacred Mount Kailash. The Tibetan name Mapam Yumtso translates to "Invincible Jasper Lake" or "Victorious Lake". Religious Significance: Vindicated as a holy site in four religions: Hinduism, Buddhism, Jainism, and Bön.   It rests near its salty twin lake, Lake Rakshastal , with which it was once connected.

  The largest freshwater lake in China, The Poyang Lake is the largest freshwater lake in China, located in northern Jiangxi Province. Situated south of the Yangtze River, connected to it by a northern channel. The lake is Fed by five major rivers, including the Gan, Xin, and Xiu.   The Poyang Lake has obvious seasonal characteristics, and its water level goes through four water periods in a year: rising, flooding, retreating, and drying . Size Changes: Size changes dramatically by season. It expands up to 4,000 square kilometers in the rainy summer and shrinks to around 1,000 square kilometers or less during the dry winter. Migratory Birds: Acts as a major winter home for hundreds of thousands of birds , including roughly 98% of the world's Siberian cranes and 90% of Oriental white storks.Best Time to Visit: November to March, when low water levels create mudflats and wetlands ideal for bird watching.

The Lake Taupō is covering a surface area of 616 square kilometers (238 square miles) on the North Island. The Lake Taupō is Located in the Central North Island (Waikato region). The lake was formed in a huge caldera created by a massive volcanic eruption roughly 26,500 years ago. Its Depth reaches a maximum depth of 186 meters (610 feet). Its Outflow flows into the Waikato River, New Zealand's longest river.   Some Major New Zealand Lakes  are: Lake Te Anau : The largest lake on the South Island and second-largest in the country (344 km²). Lake Wakatipu : The longest lake in the country (80 km long) located in Otago. Lake Hauroko : The deepest lake in New Zealand, reaching a depth of 462 meters.

  The Lake District is England's largest national park. The Lake District in Northwest England is a mountainous UNESCO World Heritage Site and England's largest national park , famous for its sweeping glacial lakes and rugged peaks. The Lakes might look peaceful, but they're a thrill-seeker's paradise too – with canyoning, rock climbing, zip lining, treetop trails and mountain bike tracks.  The East Lake District , named after the East Lake Specific Plan , covers an approximately 3,240-acre area at the southeastern end of Lake Elsinore. Highest Peak: Scafell Pike (978 meters / 3,209 feet). Largest Lake: Windermere (over 11 miles long). Deepest Lake: Wastwater (74 meters / 243 feet deep). Total Major Lakes: 16 (technically only one, Bassenthwaite Lake, is officially named a "lake"; the rest are waters or meres). Location: Cumbria, Northwest England.

  The third lowest lake in the world. The Ayding Lake is the lowest surface point in China, sitting 154 meters (505 feet) below sea level in the Turpan Depression of Xinjiang. Known as Aydingköl in the Uyghur language, which means "Moon Lake" because its white salt crust shines like a bright moon. Current Status: Mostly a dried saltpan and salt marsh with thick crystal salt crusts, though seasonal meltwater sometimes creates shallow pools. Dimensions: Measures about 40 kilometers (25 miles) across from east to west and 8 kilometers (5 miles) from north to south. Extreme Climate: Holds records for extreme heat, with temperatures reaching up to 50.3 °C (122.5 °F). Tourism: Visitors travel to the area to see the stark desert landscape, salt crystals, and unique geographical layout

  Start your day with a refreshing morning swim in Lake Mälaren!  Join The Stockholm International Water Institute (SIWI), the City of Stockholm, Swimmable Cities and partners on Thursday, 27 August, from 06:45 to 08:00 at Marieviksbadet, Stockholm, to celebrate World Lake Day during World Water Week 2026. Together with World Water Week participants, Stockholmers and visitors—including Swedish Olympic swimming medallist Therese Alshammar—we'll celebrate the vital role healthy lakes and freshwater ecosystems play in supporting people, nature and communities. Why World Lake Day? World Lake Day celebrates the importance of lakes and freshwater ecosystems to people, nature and society. Lakes provide drinking water, support biodiversity, strengthen climate resilience and create opportunities for recreation and wellbeing. The day is an opportunity to celebrate what healthy lakes make possible while highlighting the importance of protecting freshwater ecosystems for future generation...

Human activities are threatening the sustainable use of lakes and reservoirs around the globe. These sources of water are critical components in the ecological system. They provide habitat, sanctuary, and food for many species of fish and wildlife and are also a source of many beneficial uses for humankind. They provide drinking water; they are a source for process water to a myriad of industries, and their waters are used to generate power. Lakes and reservoirs provide food, navigation services, and recreational opportunities. Information and case studies reviewed in this paper indicate that the resource is at risk from over-enrichment, over exploitation, contamination by toxics, and water diversion for unsustainable agricultural uses. As a result, options for reginal development are being curtailed, human populations are being uprooted, and future generations of people are being impacted by materials polluting lake waters. This paper calls for immediate action to reverse the degrada...

The Comprehensive guidance on protecting and restoring lakes is detailed in theWorld Bank technical paper Restoring and Protecting the World's Lakes and Reservoirs .  Learn about the diversity of lake ecosystems, explore their vital role in human development and planetary health, uncover the threats they face, and access tools and resources to join UNEP and partners in the mission to conserve, protect, and restore them to their former glory!  Protecting and restoring lakes and other freshwater ecosystems also form a key area of action for the UN Decade on Ecosystem Restoration, including the Freshwater Challenge. Dive into the Healthy and Productive Lakes Portal!