Benin
Benin - 2.5 Waterways Assessment
Export to PDF
Home
Benin

Waterways Assessment 

image-20240213161621-1

Benin has several rivers, the most important is the Pendjari river in  the northwest (380 km), Couffo to the southeast (170 km), Ouémé to the center and south (150 km), Niger to the north and to the northeast and finally, the Mono to the west (100 km). Some of these rivers have important affluents. It is Niger with Mekrou (410 km), Alibori (338) and Sota (250 km) and Ouémé with Zou (150 km).  

River transport is not very developed and is essentially focused on Lake Nokoue. It allows trading between the people living around the lake and the international market in Cotonou. They are mainly boat owners providing shuttle services. 

For more information here.  

Government Contact here. 

 

The Niger Basin  

Over 135 km, the Niger River is the border with the State of Niger. On this short route, the Niger has a straight line-oriented NW-SE and receives on the right back the contributions of four affluents which are from west to east:  

  • The Mékrou (10,500 km²);  

  • The Kompa Guru (1,980 km²);  

  • The Alibori (13,740 km²);  

  • The Sota (13,600 km²).  

Southeast of the Sota basin are located the high basins of Nigerian tributaries including Wara and Olil. The Ouémé (400 km of which 200 are navigable), le Mono (350 Km of which only 100 km are navigable) and the Couffo. 

  

The Pendjari basin (420 km in Benin)  

Run off from the northern slopes and highlands of the Natitingou region will converge on the Atacora boutonniere. There are three main areas of drainage:  

  • The Kounne: 550 km2 for a length of 46 km and 200 m of unevenness,  

  • The Tigou: 317 km2 for a length of 27 km and 300 m of unevenness,  

  • The Sarga: 567 km2 for a length of 48 km and 300 m of unevenness.  

  • The Kounne and the Tigou will join to form the Pendjari which will receive 22 km further Sarga.  

 

The Ouémé basin  

We distinguish the part of the Ouémé basin on the Dahomeyen basement which is called the "Ouémé Supérieur", and is located on the sedimentary formations of the coastal basin that is designated the "Lower Ouémé".  

 

The Upper Ouémé (46,500 km2 for a length of 523 km)  

We can divide the hydrographic network of Upper Ouémé into three entities:  

The left bank network, located east of the north-south axis consisting of the Alpouro and then the Ouémé valleys.  

The north-west network, on the flanks of the reliefs of Atacora and Alédjo  

The Zou basin.  

Some of the most important tributaries are from upstream to downstream:  

  • The Alpouro: 2 010 km2 for a length of 86 km,  

  • Yerou Maro: 2 590 km2 for a length of 120 km,  

  • The Biffa: 1 990 km2 for a length of 78 km,  

  • Okpara: more than 10 000 km2 for a length of 362 km.  

 

The lower Ouémé  

After its confluence with the Zou, Ouémé deeply cuts the formations of Continental Terminal. The slope of the river then becomes extremely low (5 m of unevenness over 85 km) and the Ouémé Valley presents itself as a large flood zone where the hydrographic system is very complex. A river, the Sô on the right back, has a course parallel to the Ouémé with which it is connected by different arms sometimes diffluent, sometimes tributaries: Zounga, Agbagbe, Ouovu and Zouvi. It is this ensemble that forms the delta of Oueme. Sô and Ouémé flow into Nokoué Lake respectfully around Ganvié and west of Porto-Novo to the east.  

Nokoué Lake communicates with the sea through the channel of the Cotonou lagoon and the Porto-Novo and Nigeria lagoons.  

On highly permeable bar earth plateaus, there is almost no hydrographic network. In the Lama Depression very flat, the hydrographic network is very degraded. There are many areas of endoreism.  

 

The Couffo basin (190 km)  

The Couffo has its source in Togo at 240 m above sea level, near the village of Tchetti. It flows into Lake Ahémé 24 km long and whose outlet is the lagoon complex "Bouches du Roi".  

The tributaries are of minor importance and have high slopes (from 5 to 13 m / km).  

Let's quote from upstream to downstream:  

  • The Aiokpe: 47 km2  

  • The Gougou: 36 km2  

  • The Honve: 166 km2  

  • The Agougan: 90 km2  

  • The Dra: 147 km2  

On the land of the bar and the Cretaceous and Eocene formations, the hydrographic network is non-existent.

  

The Mono Basin (148 km in Benin) and the Sazue (150 km)  

On the 148 km of its route in Benin, the Mono cuts the formations of the Continental Terminal and flows in a wide alluvial valley (about 10 km). The slope of the bed becoming very low (0.06 to 0.4 m / km), the Mono describes large meanders through flood zones before joining the lagoon system of "Bouches du Roi".  

 

In the alluvial valley exists a degraded and complex hydrographic network, with the presence of ponds and lakes on its periphery. Two of the most important are Togbadji and Toho lakes.  

Moreover, the Beninese territory has in the littoral zone, an important lacustrine and lagoon network of approximately 270 km2. The main lakes and lagoons, from west to east, Lake Toho, Lake Togbadji, Lake Ahémé (78 km2), Lake Nokoué (135 km2) and the lagoon of Porto-Novo. Further north of this range are very small dam lakes in the Ouémé and Mono plains. These different morpho-climatic and fluvial elements contribute to the formation of exploitable soils for agriculture. 

Jump to top