710 articles
Meuse
The Meuse (Maas) is a ~950 km rain-fed European river rising on the Langres plateau, flowing through France, Belgium and the Netherlands to the Rhine delta; canalized, internationally managed, hit by record 2021 floods.
Mezen
Mezen (Мезень), river in the Komi Republic and Arkhangelsk Oblast, Russia; 966 km, basin 78,000 km², flows from the Timan Ridge into Mezen Bay of the White Sea; city of Mezen at its mouth.
Miami River (Florida)
The Miami River is a 5.5-mile tidal river in Miami, Florida, running from the Miami Canal to Biscayne Bay and carrying hundreds of freight vessels a year to Caribbean ports.
Middle Amu Darya
Middle Amu Darya: FEOW freshwater ecoregion 630, the middle and lower-middle Amu Darya basin from south of Urgench upstream to the Vakhsh, Kafirnigan, Surkhandarya, and Kunduz rivers, spanning six Central Asian countries, with endemic sturgeons and heavy irrigation-driven salinization.
Middle Amur
Middle Amur, FEOW freshwater ecoregion 617 (temperate upland rivers, Palearctic), the middle Amur River with Zeya and Bureya catchments in Russia and China; Bureya grayling endemic, autumn keta run extirpated, Zeya and Bureya dams reshape flow.
Middle Brahmaputra
The Middle Brahmaputra is a freshwater ecoregion covering the tropical and subtropical upland rivers of the middle Brahmaputra basin in India, Bhutan, and southeast Tibet.
Middle Missouri
Middle Missouri, FEOW freshwater ecoregion 143, a temperate floodplain rivers and wetlands region covering the middle Missouri River basin from central North Dakota to northwestern Colorado, with no known endemic fish, mussels, crayfish, or aquatic herpetofauna.
Middle Yangtze
Middle Yangtze: FEOW freshwater ecoregion 765 in China, temperate upland rivers from the Sichuan basin through the Three Gorges to the Qing River confluence; Min, Tuo, Jialing, Wu, Qing tributaries.
Middle Zambezi - Luangwa
The Middle Zambezi - Luangwa is a freshwater ecoregion in Zambia, Zimbabwe, and Mozambique, named for the dam-regulated middle Zambezi and the unregulated Luangwa River, stretching from Victoria Falls to the Cahora Bassa Gorge.
Mississippi River
The Mississippi River drains 41% of the contiguous United States into the Gulf of Mexico. Key facts: 18 million people drink its water, the 1927 flood reshaped U.S. flood control, and its nutrient runoff drives the Gulf dead zone.
Mississippi River Delta
The Mississippi River Delta is the birdfoot delta in coastal Louisiana, also called the MRD, built by Holocene delta-lobe switching. About 5,000 km² of land has been lost since 1932 due to dams, levees, subsidence, and sea-level rise.
Mississippi River System
Mississippi River System: the Mississippi River and tributaries (Missouri, Ohio, Tennessee, Arkansas, Illinois) draining about 40% of the continental US across 31 states and 2 Canadian provinces; managed for 9-foot navigation, flood control, and nutrient pollution.
Missouri River
The Missouri River, the Mississippi's principal tributary, is regulated by six federal mainstem dams (Fort Peck through Gavins Point) under the Corps' Master Manual for eight authorized purposes, with major sediment, drought, and endangered-species consequences.
Molopo
Molopo River, ephemeral southern Kalahari river rising near Mafikeng, South Africa; forms Botswana-South Africa border, joins Nossob, blocked by dunes from reaching the Orange River; basin 151,000 km2.
Monongahela River
Monongahela River: north-flowing river formed at Fairmont, West Virginia by the West Fork and Tygart Valley rivers, flowing 128–130 miles to Pittsburgh to form the Ohio with the Allegheny; 7,340 sq mi basin, nine locks and dams, coal barge route, drinking water for about one million people.
Moselle
Moselle (Mosel): major Rhine tributary rising at Col de Bussang in the Vosges, flowing 520 km to Koblenz; 28,000 km² basin shared by France, Luxembourg, Germany, Belgium; canalized international waterway.
Mun
Mun River (แม่น้ำมูล), largest Mekong tributary by area in northeast Thailand's Khorat Plateau; home of the controversial 136 MW Pak Mun Dam (1994) and moated Iron Age archaeological sites.
Mur
Mur (Mura), Central European river and Danube sub-tributary via the Drava; rises in Austria's Lungau at 1,898 m, flows past Graz, forms borders with Slovenia, Croatia, Hungary, joins the Drava at Légrád.
Murray (мурреи, rivers_lake_centerlines:54)
The River Murray (Murrundi) is Australia's longest river at 2,508 km, running from the Great Dividing Range to the Southern Ocean at Goolwa; central to the Murray–Darling Basin, Ngarrindjeri culture, irrigation, and salinity management.
Murray River
Murray River (River Murray), main river of the Murray–Darling system, Australia's longest river system. Known for low, variable flows, heavy salinity managed since 1988, and the Murray Mouth salt export.
Murray–Darling basin
Murray–Darling Basin, Australia's largest river system in the south-east, spanning five jurisdictions; governed by the 2012 Basin Plan, with water recovery targets of 2,075 plus 450 GL/y and storages at 61 percent in mid-2025.
Namak
Namak (FEOW ecoregion 447) is a Palearctic freshwater ecoregion covering the endorheic basin of Namak Lake, a 1,800 km2 salt lake in north-central Iran, with endemic fishes and declining low flows.
Napo
Napo (Río Napo), Andes-to-Amazon tributary rising near Quito, Ecuador, flowing ~885–1,125 km through Ecuador and Loreto, Peru, into the Amazon; ~6,300 m³/s discharge, Curaray its main tributary, Yasuní and Cuyabeno protected areas.
Narmada River (नर्मदा नदी)
Narmada River (नर्मदा नदी), also Narbada, India's longest west-flowing river, 1,312 km from Amarkantak to the Gulf of Khambhat; site of the Sardar Sarovar Dam, its irrigation network, and the Narmada Bachao Andolan displacement controversy.
Narmada-Tapti
Narmada-Tapti (FEOW ecoregion 708), a freshwater ecoregion covering the Mahi, Narmada, and Tapi river basins of India draining to the Gulf of Khambhat; intense monsoon flood regime, no endemic fishes, largest river basin of Madhya Pradesh.
Naryn
Naryn (Нарын), river in Kyrgyzstan and Uzbekistan, major tributary of the Syr Darya; about 600 km long, meltwater-fed, and the site of the 2870 MW Naryn hydropower cascade including Toktogul.
Natural drainage system
A natural drainage system is the network of stream channels and land paths that collect runoff from a drainage basin and convey it to a common outlet.
Negro (river, Colombia)
Río Negro (Colombia): name shared by several rivers, including a Magdalena tributary in Cundinamarca–Boyacá (4,238 km² basin), the Antioquia Negro–Nare river, and the Amazonian Rio Negro, called the Guainía in Colombia.
Negro (river, Uruguay)
Río Negro (Uruguay): 850 km river rising in Brazil's sierra de Santa Tecla, principal tributary of the Uruguay River, dividing Uruguay north and south; basin 68,214 km2, flow 520 m3/s, three UTE hydroelectric dams, monitored for water quality since 2009.
Nelson
Nelson, here the Nelson River in Manitoba, Canada: fourth longest Canadian river, draining over 1.2 million km2 from Lake Winnipeg to Hudson Bay and anchoring Manitoba Hydro's regulated hydroelectric system.