| Ikpoba River | |
|---|---|
  Location of Ikpoba River in Nigeria | |
 | |
| Location | |
| Country |  Nigeria |
| State | Edo State |
| Physical characteristics | |
| Source | Ishan Plateau |
| • location | Edo State, Nigeria |
| Mouth | Ossiomo River |
• location | Edo, Delta States |
• coordinates | 6°03′1″N 5°39′30″E / 6.05028°N 5.65833°E |
| Basin size | 922 km2 (356 sq mi)[1] |
| Width | |
| • minimum | 10m |
| • average | 12m |
| Basin features | |
| Landmarks | Ikpoba Dam |
| Bridges | Ikpoba Bridge |
Ikpoba River is a waterway in southern Nigeria, traversing Edo State and providing resources for the inhabitants of Benin City and nearby areas. Rising from the Ishan Plateau, the river flows through Benin City and drains a basin area of approximately 922 km2 (356 sq mi). It supplies freshwater, generates hydroelectric power, and supports agricultural irrigation. The river's hydrology is influenced by seasonal rainfall variations. Baseflow contributes about 56% of its total discharge, while the remaining 44% comes from overland flow. In its upper sections, the river exhibits a dendritic drainage pattern and is sustained by groundwater from the Benin Formation, ensuring a relatively consistent flow throughout the year. Studies have detected heavy metals like cadmium, lead, and mercury, raising concerns over industrial and domestic waste pollution.
Beyond its environmental importance, the Ikpoba River holds historical and cultural significance. Since the 15th century, it has been considered a spiritual guardian of Benin City, especially after Oba Ewuare the Great was believed to have fortified it against external threats. Over time, the river has become an object of religious reverence and is often worshipped during times of crisis. Its name is embedded in the traditions of the Bini people. An infrastructure on the river is the Ikpoba Dam, initially impounded in 1975 and officially commissioned in 1987. The dam functions as a reservoir for public water supply, delivering an estimated 90,000 m3/d (37,000 cu ft/ks) of water to residents of Benin City. However, the reservoir has experienced siltation, resulting in a 23.16% loss of capacity due to sediment deposition. Periodic dredging has been recommended to maintain its efficiency and extend its operational lifespan.
Environmental issues affecting the Ikpoba River include deforestation along its riparian zones, primarily driven by agricultural expansion and urban development. The presence of pollutants from breweries, abattoirs, and sewage discharge points has impacted the river's ecology. To mitigate these impacts, the Edo State Government has initiated efforts to dredge and desilt the river, aiming to reduce flooding in low-lying areas of Benin City. Despite these environmental challenges, the Ikpoba River remains a resource for fishing, transportation, and small-scale hydroelectric power generation. Plans to utilise its hydropower potential have progressed, with a feasibility study completed in collaboration with the United Nations Industrial Development Organization (UNIDO) to generate renewable energy from the dam. The river plays a role in regional development and climate resilience strategies.