River is any natural body of water that flows from a higher altitude to a lower altitude in a channel with defined banks. Rivers, creeks and brooks are all names for water flowing in natural channels. The names are pretty much interchangeable, but it is commonly assumed that brooks are the smallest of the three, with creeks being in the middle, and rivers being the largest.
A seasonal distribution of rivers streamflow is closely related to the precipitation and evaporation regimes in their drainage areas. River types include:
- perennial or permanent rivers (always flow),
- intermittent or seasonal rivers (flow periodically),
- ephemeral or episodic rivers (flow only during and after storms).
Most of the rivers in Liberia are of perennial type however discharge in these rivers varies greatly between a wet and a dry season.
The Liberian rivers are rain-fed and discharge into the Atlantic Ocean. Six largest Liberian rivers are international rivers, which can be defined as rivers shared by two or more countries. The Mano River, the Lofa, the St. Paul, the St. John, the Cestos and the Cavalla River have headwaters in Guinea or in Sierra Leone and cross the entire Liberia territory from north-west to south east. The largest rivers in Liberia are:
| Name of the River |
River length (km) |
Total basin area (km2) | Basin area in Liberia (km2) | Basin area in Liberia (%) |
| Moa River | 475 | 19,617 | 1,730 | 9 |
| Mano River | 391 | 7,520 | 5,539 | 74 |
| Lofa River | 410 | 10,612 | 9,189 | 87 |
| St. Paul River | 495 | 20,281 | 10,991 | 54 |
| Farmington River | 153 | 5,249 | 5,249 | 100 |
| St. John River | 464 | 16,930 | 14,363 | 85 |
| Cestos River | 476 | 12,709 | 10,389 | 82 |
| Sehnkwehn River | 230 | 5,659 | 5,659 | 100 |
| Cavalla River | 861 | 30,277 | 12,240 | 40 |