The project included the construction of 5.2 km long outfall, consisting of two 3,000mm internal diameter reinforced concretepipes laid in a single trench and the third pipe in separate trench. The land section of outfall is 300m and marine section is 4,900m, and is laid in depth varying from -35m to -46m. The main activities include survey, manufacture of pipes and diffuser elements, onshore and offshore trench excavation, laying of pipelines and testing and commissioning of completed outfall.
The main items of work comprised:
Installation and testing of 36 nos 1.20 m diameter reinforced concrete load bearing bored piles with a maximum length 32m
Installation and testing of 170 nos 1.20 m diameter reinforced concrete intermediate bored piles of length between 24 and 12 m
Installation and testing of 64 nos 1.20 diameter sand cement bored piles of 10 m length.
Design, construction and removal of a watertight steel sheet pile cofferdam of 390 m length to enable excavation of maximum 15 m