Hydrological Observation Circle has been entrusted with the work of hydrological observation and flood forecasting activities. It has one division namely Middle Ganga Division 3, Varanasi which in turn is entrusted with following function-

• Carrying out hydrological observation on 52 no. of sites on various rivers in the state of Uttar Pradesh and publication of water year book.
• Flood forecasting work of 9 no of sites in Uttar Pradesh and publication of flood appraisal report.
• Water quality monitoring of rivers.

Apart from above stated functions following administrative work is also executed by Hydrological Observation Circle-

• Recruitment/Appointment of work charged staff.
• Establishment matters related to wok charge staff.