Project Name: Ocean Outfall Diffuser, Samut Prakarn
Name of Company: Wisit Engineering Consultants Co., Ltd.
Name of Associates Firm: Italian-Thai Development Public Co., Ltd.
Location: Samut Prakarn Province, Thailand
Client: Pollution Control Department
Project Cost: 404 million baht
Type of Service: Structural Engineering Design and Construction Method
Project Description: Ocean Outfall Diffuser, Contract Number SC-41 of Samut Prakarn Wastewater Management Project located at Klong Dan district, Sumut Prakarn province, Thailand, is a system of underwater tunnel and pipeline for transmitting and dispersing of treated wastewater to the sea. Several alternatives have been proposed and the inverted tunnel or siphon system, which has the least impact on the environment, is selected. The system comprises onshore and offshore shafts, tunnel, diffuser steel pipe and 100 risers.
The onshore and offshore shafts, each with an outside diameter of 11.0 meters and a wall thickness of 1.0 meter, are located 2,620 meters apart. The onshore and offshore shafts are connected by a tunnel with an inside diameter of 2.60 meters, at the elevations of -26.0 and –23.0 meters msl respectively. From the offshore shaft, the diffuser steel pipe with an inside diameter of 2.60 meters and a wall thickness of 15 mm is extended 613.5 meters offshore. The diffuser pipe is installed at 1.20 meters below seabed. One hundred risers, each with an inside diameter of 250 mm, are installed on top of the diffuser pipe and exposed 0.70 meters above the seabed.