KBC 2023| The Idukki dam is built on which river? KBC 2023, Check the answer to the question- The Idukki dam is built on which river? By Himani Budakoti - August 29, 2023 KBC 2023, Amitabh Bachchan. (Representative Image) KBC 2023, The options of the question – The Idukki dam is built on which river? A. Krishna B. Godavari C. Periyar D. Mahanadi The answer is C. Periyar.