- Overall administration in the office
- General affairs, security, service and payment
- Matters regarding budget and accounting
- Matters regarding management of public assets
- Matters regarding management of goods
- Other matters not pertaining to other departments
- Water quality management for raw water and treated water
- Maintenance of the water treatment chemicals
- Management of Water Protection Zone
- Production and operation of bottle water
- Operation of wastewater treatment facility
- Management of high pressure gas (chlorine) safety
- Cleaning of water treatment facility
- Maintenance of mechanical and electrical equipments in Yongyeon Water Treatment Plant
- Maintenance of mechanical and electrical equipments in No. 2 Reservoir and No. 4 Reservoir
- Maintenance of mechanical and electrical equipments in Sansu, Bonchon and Ilgok Distribution Reservoirs
- Safety inspection and maintenance of facilities
- Repair work and design of facilities
- Inspection and repair of conveying and supply water pipes