WATERSHED DELINEATION OF WATER LEVEL RISE FOR RICE FARMING GEOGRAPHIES IN OGOJA, CROSS RIVER STATE, NIGERIA

Ogoja serves as a critical hub for rice production in Nigeria. However, the increasing variability in rainfall-runoff patterns has led to unpredictable water level rises within the Cross River sub-basin, threatening the socio-economic stability of rice farming geographies. This study investigates watershed delineation and water level dynamics in the River Aya catchment of Ogoja, Cross River State, Nigeria. This study employs integrated modeling, combining the Soil and Water Assessment Tool (SWAT) to simulate water level fluctuations and agricultural suitability maps with high-resolution Digital Elevation Models (ALOS PALSAR 12.5 m and SRTM 30 m). The findings highlight that the watershed was delineated into 20–25 sub-basins, revealing a well-developed dendritic drainage system. Spatial analysis shows that downstream and central sub-basins are highly vulnerable to flooding, while upstream areas are runoff generation zones. Agricultural suitability mapping identified floodplains as highly suitable for rice production under controlled hydrological conditions but prone to significant yield loss during extreme flooding events. The study emphasizes the necessity of integrated watershed management, improved drainage infrastructure, and climate-resilient farming strategies. It concludes by advocating for engineering interventions under the World Bank-funded Sustainable Power and Irrigation for Nigeria (SPIN) project and the adoption of Sub1 varieties to enhance agricultural resilience.