| English | Spanish |
| Apaporis river caiman | caimán del río Apaporis (Caiman crocodilus apaporiensis) |
| Chinese river dolphin | delfín de agua dulce chino (Lipotes vexillifer) |
| common batagur, river terrapin, tuntong | galápago indio |
| Convention on cooperation for the protection and sustainable use of the river Danube | Convenio sobre la cooperación para la protección y el uso sostenible del Danubio |
| Declaration on the cooperation of the Danubian countries on problems of the Danubian water management, in particular for the protection of the River Danube against pollution | Declaración sobre cooperación de los Estados danubianos en materia de gestión hidrológica del Danubio, en particular para la protección del río Danubio contra la contaminación |
| Declaration on the cooperation of the Danubian countries on problems of the Danubian water management, in particular for the protection of the River Danube against pollution | Declaración de Bucarest |
| Indus river dolphins | delfines de río o de agua dulce (Platanista minor) |
| international river basin | cuenca fluvial internacional |
| international river basin Land area drained by a river and its tributaries whose waters are situated in and utilized by two or more countries | cuenca fluvial internacional |
| mouth of river | desembocadura de un río |
| Okavango and Chobe River System Agreement | Acuerdo relativo a los sistemas fluviales del Okavango y del Chobe |
| Organisation for the Development of the Senegal River | Organización para el Desarrollo del Río Senegal |
| river authority | comisario jefe de aguas de la Cuenca Hidrográfica |
| river basin development | desarrollo de una cuenca fluvial |
| river basin development | desarrollo de cuencas fluviales |
| river basin development Any growth, maturation or change in an area of land drained by a river and its tributaries | desarrollo de cuencas fluviales |
| river basin district | demarcación hidrográfica |
| river basin management plan | plan hidrológico de cuenca |
| river bed | lecho de río |
| river bed The channel containing or formerly containing the water of a river | lecho de río |
| river board | comisario jefe de aguas de la Cuenca Hidrográfica |
| river catchment area | cuenca |
| river channelling | encauzamiento de ríos |
| river channelling The alteration of a natural stream by excavation, realignment, lining or other means to accelerate the flow of water | encauzamiento de ríos |
| river disposal | vertido al río |
| river disposal Discharge of solid, liquid or gaseous waste into a river | vertido al río |
| river dolphins | delfines de río (Platanistidae) |
| river landscape | paisaje fluvial |
| river management | gestión de río |
| river management The administration or handling of a waterway or a stream of flowing water | gestión de río |
| river marsh | marisma fluvial |
| river marsh | marjal |
| river marsh | llanura aluvial |
| river mouth | desembocadura |
| river mouth | desembocadura de un río |
| river policing | guardería fluvial |
| river pollution | contaminación fluvial |
| river pollution The direct or indirect human alteration of the biological, physical, chemical or radiological integrity of river water, or a river ecosystem | contaminación fluvial |
| river transport | transporte fluvial |
| river transport Transportation of goods or persons by means of ships travelling on rivers | transporte fluvial |
| river water | agua de río |
| river water Water which flows in a channel from high ground to low ground and ultimately to a lake or the sea, except in a desert area where it may dwindle away to nothing | agua de río |
| run-of-river hydro-electric power station | central hidroeléctrica de agua fluyente |
| Senegal River Development Organization | Organización para el Desarrollo del Río Senegal |
| South American river dolphins | sotalia de América del Sur (Sotalia spp.) |
| Southern river otter | nutria chilena (Lontra provocax) |
| Tana river red colobus | colobo de tana |
| the results of measurements of the radium-226 content of river water and river muds and silts | resultados de las mediciones del radio-226 presentes en las aguas y en los fangos fluviales |
| white-eyed river martin | golondrina de anteojos (Pseudochelidon sirintarae) |
| Yangtze river dolphin | delfín de agua dulce chino (Lipotes vexillifer) |
