Analysis of Flow Variability in Otamiri River, Imo State, Nigeria
Authors: Ibeje AO
Flow duration curve (FDC) is widely used in hydrology to assess the flow regime of a river. This paper presents the derivation of FDC for Otamiri catchment in Imo State, Nigeria. FDC was constructed from 1979-1989 mean monthly flow data, ranked from largest to smallest value, with each corresponding percentage of months for which the flow value was equaled or exceeded. The flow duration curve was obtained by plotting flow versus exceedence frequency. The derived flow duration curve was used to characterize the flow in the range from 10% to 90% of time flow is equaled or exceeded. This maximum flow and average flow were determined as 9.22 m3/s and 7.21 m3/s respectively while the power potential and installed capacity were computed as 175.38 kW and 224. 28 KW respectively. The dependable power and average annual energy generated were estimated as 102.41 kW and 1,536,357.27 kWh respectively. The reliability of hydropower generation in Otamiri catchment can be assessed based on the lowest monthly flow which was estimated for Otamiri as 7.21 m3/s. The design flow was estimated as 9.22 m3/s. This study has demonstrated that FDC is useful in water resource assessment of river catchments.
Affiliations: Department of Civil Engineering, Imo State University, PMB 2000, Owerri, Nigeria.
Keywords: Flow Duration Curve, Otamiri Catchment, Power Potential, Installed Capacity, Maximum Flow, Average Flow
Published date: 2020/12/30