Responsibilities are as follows:
1. Planning, construction, repairing and maintenance of water control systems structure such as drainage tunnels, pumping stations and gates
2. Management of water control systems structure to prevent and resolve flood problems also drought and sea water intrusion.
3. Manage the water retention basin or monkey cheeks to be water accommodate Bangkok city
4. Planning of the water circulation to maintain the quality of the water in the canal.
5. Control the water level in the canal for navigation and tourism
6. Installation, control, repair and maintenance of drainage systems, lighting and fire protection systems in the tunnel underpass
7. Perform other related duties or assigned.

The office consists of :
1. General administration Section
1. Correspondence and general administration
2. Administration and coordination work
3. Procurement
4. Staff and discipline work
5. Finance and budget
6. Public relations
7. Supervision and facilitate of office premises and vehicles
8. Perform other related duties or assigned

2. Eastern Water Control System Section
1. Improve, inspect, supervise and operate water control structure systems
2. Control, monitor and monitor drought problems in the area, coordinate with relevant agencies, including the public, private and public sectors to enhance participation in sustainable drought resolution
3. Control and monitor the water quality in the canal, planning for water regulatory and dilution for better water quality in the canal.
4. Plan and control the water level for navigation and tourism
5. Perform other duties that are related or assigned. The section is responsible for the eastern suburban area of the Bangkok outside of the Royal Initiative water barrier (outside King’s Dike)

3. Phra Nakhon water control system Sub-office
The sub-office has responsibilities as follows:
1. Planning for water management, improvement and development of water control structure, regulating water, inspecting, supervising the water control structure and system. Water drainage tunnels and retention basin (monkey cheeks) to prevent and mitigate flood problems.
2. Control and monitor drought problems and the salinity of water in the main canal also in the Chao Phraya River, coordinate with relevant agencies in the public, private and public sectors to enhance people participation in solving drought and salinity problems sustainably.
3. Control and monitor the quality of water in canals, plan for fresh water dilution for better water quality in the canal.
4. Plan and control the water level for navigation and tourism
5. Installation, control, repair and maintenance of drainage systems, lighting systems and fire protection systems in traffic tunnels and under pass.
6. Perform other related duties or assigned, The sub-office is responsible for Bangkok area- eastern bank of Chaopraya river inside polder of the King’s Dike. The sub-office consists of:

3.1. Drainage tunnel section
1. Reduce the water level in the main canal to mitigate the inundation from heavy rain in the polder areas as well as control the water level for navigation and tourism.
2. Supervise and manage drainage tunnels, large pumping stations to work effectively.
3. Inspect, analyze and evaluate pumping efficiency, plan for repair and maintenance of pumping stations and drainage tunnels.
4. Repair and maintenance of pumps, Watergate, automatic bar screen and various devices to work effectively.
5. Clear garbage and weed storage in front of the pumping station and drainage tunnels.
6. Collect data and information of pumping: volume, hours of operation, level, garbage collected maintenance record and other responsibilities
7. Prepare action plan for preventing flood, drought and saltwater problems.
8. Perform other related duties or assigned.

3.2. Water Control Structure Section 1
1. Supervise and operate the pumping station, floodgate, automatic bar screen and various devices to work efficiently.
2. Inspect, analyze and evaluate efficiency and plan for the maintenance of the pump station and the floodgates.
3. Repair and maintenance of the pump, floodgate, automatic bar screen and various devices to operate effectively.
4. Collect data and information of pumping: volume, hours of operation, level, garbage collected maintenance record and other responsibilities
5. Management of water in the retention basin (Monkey cheeks)
6. Action plan to prevent flooding, drought and salinity intrusion problems
7. Control the water level in the canal
8. Collection and Disposal of garbage and weed at the bar screen in pumping stations and gates.
9. Manage, Control and maintenance of the traffic tunnel and underpass for drainage, lighting and fire protection system inside
10. Perform other related duties or assigned The work group is responsible for the eastern area of the Chao Phraya River(Phra Nakorn Area), north of the Saen Saeb Canal Line.

3.3. Water Control Structure Section 2
This has the same authorities and duties as the Water Control Structure Work Group 1, but responsible for the eastern area of the Chao Phraya River (Phra Nakorn Area), south of the Saen Saeb Canal Line

3.4. Engineering Section
1. Develop water management system with water control structure with innovation and modern technology.
2. Create engineering database and analyze various data for development of drainage systems and water management
3. Study, research and develop to provide water management efficiently and good standard
4. Survey, design for the construction of water-control structure systems.
5. Design drawing and cost estimation, set the details specification of the construction also request a budget allocation for construction of a water control structure
6. Control the construction of water control systems, for best quality standards.
7. Perform other related duties or assigned.

4. Thonburi water control system Sub-office
This sub-office has the same authority as the Phra Nakhon water control system Sub-office but responsible for the Thonburi area (west bank of Chaophraya River) The office consists of :
4.1. Drainage Tunnel Section has the same authority as the drainage tunnel work group of Phranakorn water control system Sub-office but responsible for Thonburi area
4.2. Water Control Structure Section 1 has the same authority as the Water Control Structure Division 1 of Phra Nakhon water control system Sub-office but responsible for the Thonburi area
4.3. Engineering Section has the same authority as the engineering group of Phra Nakhon water control system Sub-office but responsible for Thonburi area