Failure of Irrigation Canal Network in Serving the Tail-End Ayacut A Case Study of Mangapuram Major under Nagarjuna Sagar Lal Bahadur Main Canal

The equitable distribution of irrigation water remains a persistent challenge in large canal systems of India, particularly for tail-end farmers. This study examines the failure of the Mangapuram Major distributary of the Nagarjuna Sagar Lal Bahadur Main Canal (NSLBC) in serving its designated ayacut in NTR District, Andhra Pradesh. A field-based survey, combined with hydraulic data analysis and farmer feedback, revealed multiple structural, hydraulic, and operational deficiencies. These include inadequate release from the head regulator, weak canal banks, dilapidated structures, seepage and vegetation-induced hydraulic losses, and unauthorized drawls upstream. Despite partial modernization under the Andhra Pradesh Water Sector Improvement Project (APWSIP), nearly 4,500–5,500 acres of ayacut remain unserved. The study recommends both engineering (redesign, lining, desilting) and managerial (PIM, monitoring, strict regulation) interventions to restore tail-end water delivery.