Obra Hydel Power Station was built on which river? [Heatheducation 2005]

Q. Obra Hydel Power Station was built on which river? [Heatheducation 2005]
Answer: Rihand river
Notes: Obra Hydel Power Station is located on the Rihand river in Sonbhadra district, Uttar Pradesh. Rihand is a tributary of the Son river. The power station is part of the Rihand–Obra power complex. Son, Ganga, and Ghaghara rivers have no direct association with this project.