Lakes and standing inland waters

Old Wives

Old Wives Lake (Cree Notekeu, "old woman") is a large shallow saline lake in southern Saskatchewan near Moose Jaw, in a closed internal-drainage basin, a migratory bird sanctuary and hemispheric shorebird reserve formerly named Johnstone Lake.

Onega

Onega (Onego, Онежское озеро), Europe's second largest lake, in Karelia, Russia; ~9,720–9,890 km², Svir River outlet to Ladoga, glacial origin, Onega petroglyphs.

Onondaga Lake

Onondaga Lake, near Syracuse, New York, is a 4.6-square-mile lake, once among America's most polluted, a Superfund site since 1994, sacred to the Onondaga Nation, now recovering after Honeywell's 2014 dredging.

Oregon Lakes

Oregon Lakes: FEOW freshwater ecoregion 124, Nearctic, xeric endorheic basins; also Oregon's 1,400+ named lakes, including Crater Lake (deepest in US, 1,932 ft) and Upper Klamath Lake.

Otsego Lake (New York)

Otsego Lake is a deep glacial lake in Otsego County, New York, directly north of Cooperstown and the source of the Susquehanna River; James Fenimore Cooper called it "Glimmerglass."

Oxbow lake

Oxbow lake: crescent-shaped lake on a floodplain formed when a meandering river cuts off a loop; fills with sediment over centuries, leaving a clay plug.

Ozero Srednye Kuyto

Ozero Srednye Kuyto (Keski-Kuittijärvi), the largest of Karelia's three Kuyto lakes in the Kem River basin: 275.7 km², 41.8 km long, 34 m deep, reservoir since 1956, with Kalevala on its northern shore.

Päijänne

Päijänne, Finland's second largest and deepest lake (95 m), a 120 km oligotrophic watercourse in central Finland; source of Helsinki's drinking water via the 120 km Päijänne Tunnel, completed 1982, with Päijänne National Park on its southern basins.

Pangong Tso (སྤང་གོང་མཚོ)

Pangong Tso (སྤང་གོང་མཚོ), also called Pangong Lake, is a ~134 km brackish, endorheic high-altitude lake at about 4,350 m spanning Ladakh (India) and Tibet (China), bisected by the Line of Actual Control and a focal point of the India-China border dispute and 2020 standoff disengagement.

Patos Lagoon

Patos Lagoon (Lagoa dos Patos), Brazil's largest coastal lagoon at about 10,360 km2 in Rio Grande do Sul, is the world's largest choked lagoon, connected to the Atlantic by a single inlet at Rio Grande and linked to Mirim Lagoon by the São Gonçalo Channel.

Payne

Payne: chiefly a northern Canadian toponym. Payne Lake (Lac Payne, Inuit Tasirruaq), 513 km2 Quebec lake draining via the Arnaud River to Payne Bay, named 1945 for meteorologist Frank F. Payne; also lakes in Alberta, Ontario, and the US.

Peipus

Lake Peipus (Peipsi, Chudskoe), a 3,555 km2 shallow transboundary lake on the Estonia-Russia border, fourth or fifth largest in Europe, with three basins, major fisheries, and persistent eutrophication.

Pielinen

Pielinen, a large unregulated lake in North Karelia, eastern Finland, about 867 km2, draining via the Pielisjoki into Saimaa; mesotrophic, humic, dimictic, frozen November to May, shaped by post-glacial isostatic tilting.

Pihkva

Pihkva, also called Lake Pskov (Russian: Псковское озеро), is the southernmost, shallowest basin of the Lake Peipsi system, a 708 km² lake on the Estonia–Russia border.

Pink Lake (Western Australia)

Pink Lake, historically called Lake Spencer, is a large hypersaline terminal lake about 4 km west of Esperance, Western Australia, whose pink color faded after decades of salt harvesting.

Plétipi

Lake Plétipi (Lac Pletipi) is one of the largest lakes of Quebec, Canada, in the remote Côte-Nord interior, with a 210-mile shoreline of spits and deeply indented bays.

Pond

Pond: a small, shallow standing waterbody (<5 ha, <5 m, <30% emergent vegetation per a 2022 definition), distinct from lakes and wetlands; globally abundant, biodiverse, and often human-made for farming, stormwater, or swimming.

Pong Dam Lake

Pong Dam Lake (Maharana Pratap Sagar) is a 1975 Beas River reservoir in Kangra, Himachal Pradesh; a Ramsar wetland and sanctuary hosting 45% of the world's wintering bar-headed geese.

Possum Kingdom Lake

Possum Kingdom Lake: Brazos River reservoir in Palo Pinto County, Texas, formed by Morris Sheppard Dam (completed 1941), the first water supply reservoir in the Brazos basin, run by the Brazos River Authority, 538,139 acre-feet, known for clear water, striped bass, and golden alga fish kills.

Poyang

Poyang, also called Pengli Lake (鄱阳湖), is China's largest freshwater lake, in Jiangxi Province about 50 km north of Nanchang, draining into the Yangtze River.

Pulicat Lake

Pulicat Lake (Pulicat Lagoon) is India's second largest brackish water lagoon after Chilika, on the Coromandel Coast across Andhra Pradesh and Tamil Nadu, about 450–460 sq km, fed by the Swarnamukhi, Kalangi, and Arani rivers, hypersaline, and a major migratory bird and fishery habitat.

Put-in-Bay, Ohio

Put-in-Bay is a village on South Bass Island, Lake Erie, Ohio, three miles offshore. Known for the 1813 Battle of Lake Erie, Perry's 352-foot peace memorial, ferries, and tourism-only economy.

Pyaozero

Pyaozero (Пяозеро; Finnish Pääjärvi) is a large freshwater lake in northern Karelia, Russia, part of the Kumskoe reservoir system on the Kovda River and one of Europe's largest lakes.

Pyasino

Pyasino (Пясино), glacial lake in Krasnoyarsk Krai, Russia, 20 km north of Norilsk; 735 sq km, average depth 4 m; drains via the Pyasina River to the Kara Sea; heavily affected by Norilsk mining pollution.

Pyhäjärvi (lake, Finland)

Pyhäjärvi (Säkylän Pyhäjärvi) is a 155 km² shallow lake in southwestern Finland, its largest lake, a mesotrophic, highly productive vendace and whitefish fishery under protection since 1995.

Pyramid Lake (Los Angeles County, California)

Pyramid Lake (Los Angeles County) is a 1,360-acre State Water Project reservoir on Piru Creek formed by Pyramid Dam (1969–1973), serving Castaic Powerplant and offering boating, fishing, and camping near Castaic, California.

Pyramid Lake (Nevada)

Pyramid Lake (Nevada), also Cui-ui Pah, is a 453 km² terminal saline lake on the Pyramid Lake Paiute Reservation northeast of Reno, the largest remnant of Lake Lahontan, fed by the Truckee River, home to the endemic endangered cui-ui and record Lahontan cutthroat trout.