Commercial navigation along the rivers of El Salvador is almost nonexistent. The country's largest river, Rio Lempa, connects a network of over 150 smaller streams that are used for local transportation and commerce. The river is navigable only through short disconnected segments, by small shallow draft vessels.
The country has four large river basins and seven smaller river basins that drain the Pacific Coastal Cordillera. The four large river basins are:
- Rio Lempa basin
- Rio Goascoran basin
- Rio Grande de San Miguel basin
- Rio Paz basin
The Rio Lempa is the largest and most important river in El Salvador with its basin covering an area of 18,246 square kilometers (km2). Of this area, 10,255 km2 are in El Salvador, 5,696 km2 are in Honduras, and 2,295 km2 are in Guatemala. The Rio Lempa is also the largest river system in Central America with its water used mainly for hydroelectric power. As mentioned previously, there are three significant manmade reservoirs on the Rio Lempa which store enormous quantities of water for hydroelectric power generation. They are the Embalse Cerron Grande (135 km2 surface area), Embalse Presa Cinco de Noviembre (20 km2 surface area), and Embalse Quince de Septiembre, also called Embalse del San Lorenzo (35 km2 surface area). In addition, the Embalse del Guajoyo is a small reservoir on the Rio Desague in northwestern El Salvador that is also used for hydropower. Discharges from the reservoirs control the flow of the Rio Lempa. The average flow of the Rio Lempa is about 153 cubic meters per second (m3/s) from the Embalse Cerron Grande reservoir, about 197 m3/s from the Embalse Presa Cinco de Noviembre reservoir, about 329 m3/s at the Rio Torola confluence, and about 362 m3/s at the Cuscatlan Bridge on the Pan American Highway. The Rio Lempa receives domestic and industrial wastes from population located along its western margin and a high concentration of sediments from deforested zones along the eastern margin.
The seven smaller basins are:
- The coastal area between the Rio Cara Sucia and Rio Copinula;
- The coastal area between the Rio Sensunapan and Rio Banderas;
- The coastal area between the Rio Pululuya and Rio Comalapa;
- The Rio Jiboa basin;
- The coastal area between the Rio Jalponga and Rio El Guayabo;
- The coastal area between the Rio El Potrero and Rio El Molino; and
- The coastal area between the Rio Grande de San Miguel and Rio Sirama.
All rivers in El Salvador eventually discharge into the Pacific Ocean.
El Salvador has four main lakes:
- Lake Coatepeque, the largest, is a volcanic lake located 18 km south of the city of Santa Ana. It covers an area of 24 km2 and has a depth of 115 meters. Lake Coatepeque is also located at an altitude of 745 meters.
- Güija Lake, shared between El Salvador and Guatemala, is located in the northwest border of El Salvador and east of Guatemala. It is located at an altitude of 430 meters above sea level and covers an area approximately 45 km2.
- Lake Ilopango, of volcanic origins, measures 72 km2 and constitutes one of the largest water reserves and a beauty of El Salvador. Located 16 km from San Salvador and 440 meters above sea level, it reaches depths of 230 meters.
- Lake Olomega has the largest reserve of fresh water. Its length is 24.2 km2 and is located 15 kilometers southeast of San Miguel. It is fed and drained by the Rio Grande of San Miguel and its current state is eutrophication. Its jurisdiction is shared by the municipalities of Chirilagua (San Miguel) and El Carmen (La Union).
For more information, please see the following link: 4.1 El Salvador Government Contact List
There are no important river/lake ports in country.