The Banks of the Sebou River

The Sebou river is the main stream of the basin. It is the largest North African river by volume : being about 500 km long, it has an average water flow of 137 m³/s.

The network of the basin covers an area of 40,000 km² , encompassing 4 regions and 17 provinces in Morocco. The basin is of vital socio-economic importance: being home to nearly 20% of the population, it is essential to the livelihood of over 6.2 million people, and its agricultural and industrial outcomes contribute significantly to the national economy.

However, many of these developments have negatively impacted the basin's remarkable ecosystems, which contain important wetlands, including Ramsar sites, national parks, and many other areas of biological and ecological interest.²

The perennial stream network - which is where water is naturally present all year round - of the Sebou basin is significantly different from the hydrographic network as a whole. The course of the Sebou river and its tributaries are irregular in space and time; the High Sebou is characterised by a perennial flow, while other tributaries follow a seasonal regime depending on precipitations, with the occurrence of important floods.³

Many of the areas of the basin are important ecosystems. Some are also home to freshwater animal and plant species that are threatened with extinction.

Amongst these important ecosystems we count national parks as well as Ramsar sites. Ramsar sites are wetlands that have been designated to be of international importance under the Ramsar Convention. This intergovernmental treaty provides the framework for national action and international cooperation for the conservation and  wise use of wetlands and their resources. 

Besides, several Key Biodiversity Areas (KBA), including 4 freshwater KBA are present in the region.

These areas are sites contributing significantly to the global persistence of biodiversity in freshwater ecosystems. In the Sebou basin, some of these areas intersect with Ramsar sites, protected areas and sites of biological or ecological interest.

During the summers of 2018 and 2019, a team of experts visited the southeastern part of the basin to assess the status of KBAs candidates and surrounding areas, by prospecting the occurrence of species of fish, odonata, molluscs, crabs and plants.

The native freshwater species recorded focused on aquatic plants, molluscs (bivalves and gastropods), crabs, fishes and odonata. The South and East of KBA Oued Imouzzer Kandar in addition to the central-east of KBA Oued Tizguite and Oued Ouaslane presented a notable richness of native species, specially aquatic plants.

Some areas proved to be worth of special concern due to the presence of threatened freshwater species. Such was the case of the KBAs of Oued Bouhlou and Oued Tigrira and their surroundings.

2. The area explored close to the KBA Oued Tigrira, with its high richness of odonata, molluscs and aquatic plants. In addition, 5 threatened aquatic plant and 6 threatened molluscs were recorded.

3. The main channel of Oued Sebou, with its high richness of freshwater fish and odonata. In addition, downstream of Allal Al Fassi Dam and on Oued Sidi Harazem (a tributary of Oued Sebou below the dam), the area hosts at least 4 threatened species, including Unio foucauldianus (Critically Endangered).

4. Some areas of the FKBA Oued Tizguite and Oued Ouaslane, with a high richness of odonata, aquatic plants and molluscs.