The Lower Ganga Basin Organization, CWC, Patna has been mandated for Hydrological observation &Flood Forecasting work through its offices spread over Bihar, Uttar Pradesh and Jharkhand. The main activities of LGBO are as under-

• Hydrological observation on river Ganga & its tributaries in the state of Bihar, Uttar Pradesh, Jharkhand & some part of West Bengal.
• Flood forecasting (level and inflow) in the river Ganga and its tributaries in Bihar, Uttar Pradesh, Jharkhand & some part of West Bengal.
• Appraisal of medium irrigation project in Bihar & Jharkhand.
• Monitoring of Irrigation and Command Area Development (CADWM) project in Bihar & Jharkhand.
• Examination of project proposal for Central Assistance of Major & Medium Irrigation Projects, Repair, Renovation & Restoration (RRR) of Water Bodies projects and Minor Irrigation projects under PMKSY in Bihar & Jharkhand.
• Morphological studies (Cross Sectional survey) of Ganga, Gandak, Kosi ,Ghaghra& Mahananda Rivers.

It has three Circle level / Directorate level offices as under-

1. 1.Monitoring Directorate, CWC, Patna / Hydrological Observation Circle, CWC, Patna - Headed by Director.
2. 2.Hydrological Observation Circle, CWC, Varanasi - Headed by Superintending Engineer
3. 3.Monitoring & Appraisal Directorate, CWC, Ranchi - Headed by Director.